Mark didn't want to deal with his friends or family finding out about the modified portal device just yet. He felt like showing it to them without it ever having a field test before would be a bad idea. The device needed to be tried out first, in someplace private. Luckily Mark knew the perfect spot.

The mall. While at first that might not seem like a great choice, being packed with so many people and all, Mark had a plan. Near the food court was a bathroom with a spacious handicapped stall, big enough for him to create a human-sized portal without anyone else seeing. He could try out his device in privacy.

Of course that was only half the reason why Mark picked this location. The other reason why was because this bathroom was unisex, meant for families to use. Mark was kind of a pervert and was secretly hoping that when he shrunk himself with the portal device he would get a chance to see some ladies with their pants off. He wasn't into scat or anything but he enjoyed a nice round ass when he sees one. This was one of the few places he could remember that even had a unisex bathroom and he was giddy to do the testing here.

As Mark walked through the crowded mall he held the device in his pocket. This was his best idea ever, and it was like the portal device was his good luck charm. He grinned to himself as he had almost arrived at the unisex bathroom.

That's when he saw her. A stunning teen had just walked out the restroom, her long blonde hair trailing behind her. Her hazel eyes matched her short-sleeved shirt which was low-cut enough to expose a tiny amount of her generous D-cup breasts. She had a cute face, a thin waist, and wide, wide hips.

Mark walked past her trying to play it cool, but then once he got a few steps behind her he causally spun around to get a good look at her ass. Her butt was huge and shaped perfectly. She was wearing tight yoga pants with the words "NERF THIS" written across her cheeks. Mark gave himself a moment to watch her butt wiggle as she walked. The large ass halves seductively moved up and down rubbing against each other. Mark was definitely an ass man, and after seeing this girl he wanted to use her butt as a pillow, wake up, and eat breakfast on it.

After that moment of bliss he continued on to the bathroom, the view of that big butt still hanging in his mind. Lucky for him the large handicapped stall was empty so he took it. The toilet seat was still warm! No one else was in the bathroom so it could only be warm from that girl's ass!

"So that girl... was just here." Mark thought to himself. "Her huge ass had just..."

He sniffed the air, a faint earthy scent had been leftover from her deed. Things were starting to feel really perverted for Mark, this was exactly why he loved unisex bathrooms. He could bet that there were plenty more girls in this mall that were just as hot as the one he passed by. With any luck another one might come into this bathroom, and he could shrink himself and peep on them doing their business. He could even use the portal device to watch from above, or behind on the pipes!

Getting out his "lucky charm", the portal device, Mark created a large portal on the wall and a tiny one to exit from. He set himself to be half an inch tall. Feeling confident he walked through the large portal. Was the device's inaugural test a success?

Mark fell into the toilet with a big splash.

"Okay, that was weird. I don't remember putting the exit portal above the toilet, gross."

His clothes seemed to also have dematerialized after passing through the portal, which was another bug he would need to fix later. After all that build-up it seemed like the experiment was a complete failure. With a heavy sigh Mark decided to portal back home. He had no desire to stay naked and shrunken inside a toilet. He would portal to his bedroom, shower, and put on a clean change of clothes. It was Saturday so he could always try the mall again tomorrow.

The device was still in his hand underwater. He pulled it out and was about the set new coordinates but the display was scrolling an error message.

"OVEREXPOSURE TO H2O. SPACE-TIME FLUCTUATION DETECTED. TIME IS REVERS-"

And then it shut off. This was bad. The device could luckily self-charge over time but that could take hours. Also what was with the that error message? Mark was thinking about it but then the toilet water began to stir. The pool around him was draining and he was being lowered towards the bottom. Oddly enough the streams of water coming from the upper rim weren't filling the toilet, but rather sucking up the water. But that didn't make sense. Water can't just flow upwards by itself in open air, that's impossible.

Then it clicked. Time was moving backwards around him. That's what Mark's device was trying to tell him. It had malfunctioned and now everything around him was happening in reverse order. A giant figure of a girl walked backwards into the stall closing the door in front of her. Her movements seemed odd to Mark as they were all backwards. She bent down to place her purse on the floor when really she was just picking it up before leaving. Her giant butt stuck out above the toilet bowl and Mark recognized the words "NERF THIS" emblazoned across the yoga pants. It was the blonde girl from earlier! But if Mark had just seen her leave the bathroom and time was moving backwards then...

"Oh shit!" Mark yelled and a twisting tornado of murky water and dirty paper emerged from the toilet drain. His half an inch tall body was swept up in the disgusting mess of piss and shit. Huge masses of crap collided with him, threatening to hold him down under the yellow water. The violent twister ended as quickly as it began and Mark used the calm moment to desperately climb a floating wet mound of toilet paper.

Mark coughed up some pee from his mouth, he had nearly drowned. Breathing in for the first time made him gag. The smell of such a enormous amount of poop was overpowering. Compared to him the logs were as big as tree trunks. Looking skywards he saw the girl reaching to flush the toilet, which was the cause of that horrific event.

Then she turned around and peeled off her tight pants exposing her massive ass. Really it was her putting her pants back on but it looked nearly the same. Mark normally could appreciate how sexy her perfect ass was, how shapely it looked while being so huge, but right now he wanted to cry. He knew what was going to happen next. This was not what he wanted.

The giant ass lowered and covered the toilet seat, along with covering Mark in darkness. The only way he could see was a small beam of light coming from between her soft legs and pussy. Her massive cheeks spread open as she sat and he could see her puckered butthole. It winked at him as if to say "hello, I'm going to be eating all that yummy crap you're standing in." Mark knew it was only a matter of time.

He tried yelling "HEYYYY! DOWN HERE! HELP!" but there was no way she could hear his small voice.

More light filled the bowl as a humongous hand came down. The toilet paper Mark was standing on knocked him off. It levitated upwards and returned to her grasp. She rubbed it against her anus, and when it was done the hole had become more filthy. She returned the paper to the roll as if nothing had happened and repeated the process, smearing her backdoor with more and more shit and giving her pussy a quick wipe. Soon Mark was left treading the pissy water, he had not dared to climb any of the bundles of crap that floated nearby.

The asshole looming above twitched and then gaped itself open revealing the girl's dark colon within. Mark gulped at the sight in fear, he knew what was about to happen.

A giant turd next to him rose out of the water with a splash. It made contact with her anus and snaked it's way back inside. Soon more monolithic masses of feces flew out of the lake of pee and up to the ass above. Mark saw up close how a girl's asshole flexed and contracted when she was squeezing turds out. The wrinkled hole was eating shits at a quick pace, chewing the logs as they were sucked within. Mark had to dodge the shit or risk being stuck to one and pulled inside with them!

----

Back in the normal flow of time, the girl was sitting on the toilet patiently letting her ass take a big dump. Her name was Jen, and she was totally oblivious that she was torturing the poor boy lost under her butt, essentially drowning him in her shit. Her plump ass cheeks were so big that they couldn't entirely fit on the seat, they spilled over the sides. Wiggling her hips a bit she spread her ass more on the toilet. She let out a soft sigh, relieving all that built up pressure inside felt good. It felt like her digestion cycle had been acting up and now she could just let loose.

----

Returning to Mark's experience, to him it looked like most of the excrement was gone. The burning smell was going away as the poops returned to their home. Mid-dump farts were sucked inside the bulging anus creating a loud inverse thunderclap. Even the filth around the rim of her anal ring was slurped inside and soon the dump had never happened.

Mark was still at the mercy of the giant girl, stuck wading in her gross lukewarm yellow water. The pool rippled and began to splash into a powerful stream of pee that shot upwards to her pussy. Her small urethra drank up the piss with vigor. The pillar of liquid pulled in the yellow colour from the bowl and sent it shooting back up inside her. Mark panicked as he realized he was being pulled along with it. Swimming for his life he flailed and kicked away from the torrential tower. He was seconds from being swept away in it before the stream stopped.

Given the brief moment of respite Mark tried to catch his breath. He was tired from all the swimming and was glad the ordeal was over. But what would happen next? The tiny high-schooler thought about ways he could have ended up in this toilet. Looking at the giant ass above made him think of some scary theories. There's no way he could have fallen from her butt above, right?

Wrong. Gravity acted in reverse and he was thrown up into the air, just like the disgusting mess the girl had made. Mark screamed as he was flung towards the ass, the fleshy ceiling of girl butt was closing in on him. But where did he go? Or rather, where did he come from? Was it the stuffy pussy or the dark ass crack?

Mark yelled as gravity acted in reverse, pulling his half-an-inch-tall body towards the stranger girl's butthole. Her tight wrinkled pucker became larger and larger in Mark's view. Struggled as he might, he couldn't stop the invisible forces from pulling him there. If fate had it that he came from this girl's ass, since time was playing out in reverse, that's where he was doomed to end up.

The anus opened wide, which seemed unnatural until Mark heard a blaring sound. A giantess-sized fart played out in reverse all around his tiny body. The weird inverse sounds of the girl's bassy release were so loud they felt like they were going to shatter his eardrums. Warm gusts of fetid air converged around the anus pulling him inside with them. She must have farted him out her ass and into the toilet before taking a dump! Now he was being farted back inside in reverse!

Mark was helpless as the smelly tornado sucked him past the girl's massive butt cheeks and straight to her asshole. It sucked in all of her gas violently, only stopping for a moment when it touched Mark's head. He could feel the intense vibrations of the anus farting as it swallowed his body. Hot whips of air tore past him while the giant shithole's muscles chewed him up. Mark screamed in pain, it was like he was being eaten by a fleshy blender. He remained lodged in her gassy hole until the fart finished, flinging him inside with an odd-sounding pop. The poor pathetic boy was now trapped inside the giantess's rectum.

Luckily for Mark the humongous turds that he had to deal with earlier were sucked deeper inside the girl, much farther than he was. Unlucky for him was now he was trapped inside a whirling bubble of hot death. The girl's blazing hot gas swirled around in her rectum leaving Mark with nothing to breathe but rancid unfarted air. Immediately he gagged and choked, slamming his fists on the "ground" in pain. The walls that surrounded him were a slimy shit-stained tunnel made entirely of fleshy material. Mark writhed in pain as the horrid flatus burned itself into his lungs. The sweltering heat inside the ass was slowly sapping his energy. This was not an environment where any human was meant to survive.

The anal walls quivered and undulated around his body, slathering him with sticky anal juices. Their movements created an open passageway into the colon for the gas to travel back inside. The miasma of smell drifted away from Mark, and with the gassy bubble gone the rectum closed in around him. The puffy hot tunnel of flesh didn't smother him, but instead held him in place like a piece of poop. Runny anal juices overflowed and slid into his gasping mouth.

"Fuck, it tastes so bad!" he sputtered. "I have to get out of here!"

He wanted to turn himself around and climb out of this hellhole but there was no chance. He could barely wriggle under the weight of this giant girl's ass. Suddenly he felt the world shake and turn. She must be moving!

Trapped as he was inside her rectum he could feel the movements through her body incredibly well. He felt her pulling her yoga pants up. She was peeling the stretchy material off her wide ass in reverse. After wiggling her pants on, the slippery butt walls that wrapped around Mark's body clenched down on him HARD. She had been holding in her gas all the way to the toilet! Mark's chest was being crushed so hard he could barely wheeze in his next breaths.

Through the tightened ass muscles he could feel her pounding steps as she walked backwards out of the unisex bathroom. Mark couldn't see where she was going but by counting the steps he was able to figure out how far she traveled. Unknown to her a few guys were staring at her walk, their leering eyes drawn to her sexy ass. Hers was so big that her cheeks bounced slightly as she walked, wobbling sexily back and forth. A lot of guys wished they could feel it, even for a second. Unknown to those people however, Mark had been granted that wish a thousand times over, and he was feeling her ass in the most horrible way imaginable.

It was only a few dozen steps before she stopped walking so it had to be somewhere close by, most likely the food court. Mark turned out to be correct as she sat back down and began to start the creepish act of eating lunch in reverse. As her stomach bubbled back to life and returned her chewed food, her whole digestive system reawakened. Distant gurgles haunted Marks ears, the sounds of what he might end up being subjected to later. The poor man was helpless and scared inside the sexy giantess. He was too afraid to realize she was slowly leaning her hips to one side.

It started when he caught a whiff of a strong smell. He could barely breathe while being constricted by her rectum, so the slight harsh change in air quality got his attention immediately. The strong odor heralded a much worse problem as a second rumbling fart made it's way toward him. The searing gas was sucked inside her greedy anus blasting Mark with the dirty air she expelled in the past. The new torrent of disgusting gases was pulled inside the girl and exploded into Mark's small form. More horrible than the smell or volume was the pulling effect it had on him. He was being blown inside along with the fart, out from her rectum and deeper into her colon. Mark grabbed at the slippery anal walls, trying anything to stop himself from being sucked further inside.

"NO! STOP! NOOOOOOOO!" he yelled, his horrified screams easily drowned out by the noisy fart.

The flurry of gas pulled him deep inside until he couldn't see light anymore. The wind and sound died off and the bowel walls went back to holding him in place. After that terrifying experience the foul odor inside the ass had doubled. Mark coughed and struggled, now the atmosphere was twice as humid. It felt like the moisture of her gas was sticking to his sweat. He was freed from the oppressive force of the muscles she was using to hold in her gas, but was what cost? He was even farther up shit creek without a paddle. He had to think of a way to escape this girl who was unawarely torturing him and he had to do it now while her bowels were calm.

But were they? Only a few seconds after her rank fart was blasted inside another one came. Millions of smell particles that had been dispersed from the girl earlier found their way back to her sexy butt, regaining their lost heat and fresh stench along the way. Like a vacuum the huge booty sucked in the gas between its plump cheeks. As the air squeezed through the heaving mounds of butt flesh it created a soft bubbly sound, only to be heard by its owner. The fart wormed its way toward Mark and sucked him even deeper inside the colon's depths.

The ride didn't stop there. A massive chain of farts blasted inside the bowels and assaulted Mark. The anal chamber twisted and groaned as multiple gusts of methane made their way through. Each one pulled him more and more inside, gulping him down the ass tunnel like it was a throat. The deeper he went the hotter it got, and his poor body was coated in anal slime along the way. Mark couldn't do anything to fight back his descent. He could only imagine his captress, contently eating at the mall, firing off farts with no idea that her ass was sentencing a man to death.

----

Back in Jen's timeflow she was halfway through eating her double burger when she felt her intestines rumble again. Cautiously she lifted a hefty ass cheek to the side and let her gas slowly trail out. Her rotund butt cheeks vibrated as the chain of farts bubbled through them. Muffled sounds of an angry trombone sputtered from her anus, announcing her gastric problem. No one else in the mall seemed to notice her unladylike display.

Jen sipped on her soft drink and plopped her butt back down. It felt really nice to feel some release from her ass but now she felt like she had to poop. Little did she know the tiny blockage that was tickling her backdoor was actually Mark, and the way her anus clenched on his tiny body was suffocating him. Standing up, Jen left her food behind and headed to the unisex bathroom.

----

The painful winds died down and her pace slowed to a standstill. Mark had no idea how deep inside he was now. He was waist-deep in grimy sludge trapped among several bubbles of girl flatus. The smell was heavy and weighing down on him, he didn't know how much longer he could breathe for. How could he have ended up in a situation this terrible? Who knew a girl so cute and sexy looking could fart such monsters? Just then there was an ominous inverse groan. Mark howled in anger.

"What next? What could POSSIBLY HAPPEN NOW?"

What he was met with was a tremendous booming sound that rang out like the world's largest lawnmower. The mother of all farts echoed through the happy girl's bowels and exploded on the shrunken man within. It was easily the size of three of her previous releases and it made the air inside four times as thick. Even though her turds weren't touching Mark the smell that attacked his nose made him feel like he was trapped inside of one. It smelled that bad. The fart bulldozed him deep within her anal shaft, to where it felt like the point of no return.

----

Right as Jen sat down to eat her new burger and before her chain of farts is when it happened. She was minding her own business about to dig in to her delicious meal when a huge fart ripped out her ass. The massive bubble of gas had caught her completely off guard. Jen wrinkled her nose at the smell. It was awful. She waved her hand around her seated rump, hopefully dispersing the scent before anyone else could smell it. Kind of embarrassed, the gassy girl started eating.

----

Mark laid there. Trapped and beaten inside a giant ass. The aroma of past meals bearing down on him like heavy blankets. Was he going to be one of those meals? If this kept on Mark was going to be sucked through her digestive system and most likely die. Could he seek a way out?

By all accounts, Mark was fucked. He was trapped inside a giant girl, hopelessly far up her bowels, and surrounded by heavy farts. With the flow of time stuck in reverse, exclusively effecting his shrunken body, he was doomed. The only way to go from here was back up her intestines and through her digestive system.

Mark was curled up in a ball with that thought echoing through his mind over and over again. His brain felt numb from the overexposure to methane, a result of the terrible series of farts he had just been subjected to. Her ass had effectively claimed him its prisoner, with her herself being clueless to the fact.

When he first saw the girl he was infatuated by her looks and aroused by her perfect wide ass. Now he cursed that booty, blaming it for all his current problems. That and the damn device. Some "lucky charm" it turned out to be. The damn thing ruined his life. Despair wrought over him again and he waited to die.

"It's over..." he whimpered. "I'm done. There's nothing I can do... How did I even end up in this situation?"

Wait. How had he ended up in this situation? From his perspective time was going backwards and he was sucked up inside the giant ass. But from a normal point of view her ass had farted until he was at the butthole and she pooped him out into the toilet. So how did he get inside her in the first place? Considering what had happened it didn't make sense. He didn't just materialize out of nowhere inside her bowels. His end point was the toilet, but where was the beginning?

That was simple. It hadn't happened yet. Mark thought about this. At this point the thing that put him here hadn't occurred so it could be anything. He could have been swallowed by her mouth and somehow survived. He could have been forcibly shoved up her ass. He could have even been born to life by some miracle of her broken down foods and nutrients creating the exact chemical make up of human being. He didn't want to think about that one. It meant he actually was going to die in her digestive system.

The girl had her own timeline that brought her to him. In the world of the normal timeflow where she resided she had lived her own life leading up to that point. But Mark's world was backwards. The future was set in stone and the past was uncertain. There were infinite possibilities. Any choices he made could influence the past in that regard. It was even possible that once the device malfunctioned he created a new universe in itself with every possibility unknown. And if he was the only one that could make decisions that might mean he was all powerful. Like a God. A God in his own world, covered in shit. Maybe he was going crazy from breathing in so many thick rank farts.

Of course these were all theories. There was no way to know if his actions really could influence the past or if the concept of fate was real. No way. So what could Mark do? He considered his options and possibilities. Really the best cause for him being inside her ass was the one where he was forcibly shoved up there. If he came from her stomach above he might die going through it in reverse. So how does he get himself back to her anus and unshoved up her ass?

"Hmmm, if I start crawling back towards her anus it will only mean I crawled backwards through her bowels to get here. That wouldn't make sense... but if I start crawling facing backwards from where I am now... it will mean I crawled up her butt willingly in the first place!" Mark exclaimed. He had figured out a way out!

That was his genius mind at work, the one that created the modified portal device. All he would have to do is face backwards with his butt pointed at her exit hole and crawl that way. It would look exactly like he had crawled up the giant girl's ass in the first place. If cause and effect worked the way he wanted it to, his effects could create the cause of his initial imprisonment and he could then set himself free! Probably.

There was always a chance that he was locked in here forever and no amount of made up causality and alternate universes could save him. For now he tried to push that out of his head. He needed hope right now. Getting into position he got on his hands and knees and slowly shuffled his was backwards toward her butthole.

The process was slow and dirty. He was wading in thick sludge and sticky ass slime. Leftover clumps of waste could be felt at his fingertips, making him want to gag. The more he traveled the more exhausted he became forcing him to pant and breathe the rancid air. A few times he tripped and fell into the goop, it was horrible.

The girl had moved on from eating at the mall, continuing through her day backwards. She would move around from place to place, where was unknown to Mark. Occasionally her bowels would stir and clench down on him, halting his progress. When they let up he'd be covered in a thick film of gunk, which he wiped off and kept going on his way.

It took hours for him to regain the ground he lost. Eventually his patience paid off and he was back where he started, right behind him was her colossal anus. Now what? Would it open? He gave it a kick. The smelly butthole quivered and quaked. Something was happening! Was he finally free?!

----

Jen's day was going to be a fun one. Unknown to her, the tiny boy was at her anus. It was just before noon for her now, so what was she up to for the beginning of this fine Saturday?

Jen was in the middle of taking a long shower. Trickles of water ran down her velvety smooth, milky white skin. The warm water caressed her gently in its warmth while also washing away her smelly sweat. The content girl scrubbed bubbles all over her body, cleaning every crevice. Unknown and unfelt to her, a tiny boy was escaping her darkest crevice, beneath her giant butt cheeks.

----

Mark was still inside, wriggling and squirming with all his might to be free from this hell. Digging his toes into her backdoor, he pushed as hard as he could at the wrinkled hole's skin. It was quivering something fierce and with a spontaneous lurch from her rectum it began to open up. Mark's face lit up along with the interior of Jen's poop chute. Dazzling beams of light shined from outside, illuminating the filthy, muck-filled tunnel. It might as well have been the gates to heaven, this puckered asshole. The giant anus began to pulsate around Mark's legs. He used this as his only opportunity to escape. Mark gripped the rubbery butthole's rim with both hands and pulled harder than ever before.

"C'mooooonnn! Let me ooooouuuttt!" He grunted through gritted teeth.

The asshole made a loud SPLORCH and gave him the slimy push he needed. His scrambling body slid out her hole, just like he crawled inside in reverse. It was as Mark planned, everything went perfectly. The giantess didn't have any idea either. The only surprise attribute was how wet her butt crack was.

"Are her panties wet?" Mark asked, too deeply engulfed by her ass cheeks to realize she wasn't wearing any. "Wait... is that rain? No! It's a shower!"

The tiny boy wormed his way through the two massive globes until he could stick his head outside. A rush of water was what he was met with, only it was flowing in reverse, back to the shower head. Since time was backwards the water was going up. This presented a new problem. How could he get out of here?

Mark thought for a bit until he had an idea. It was risky but... there wasn't much time. Jen was shifting her weight from side to side making her ass cheeks grind against each other. The huge fleshy booty was crushing Mark and threatening to pull him back in. He had to act now.

Throwing caution to the wind Mark popped himself out from the grip of Jen's ass and into the water. It was a gamble, but he was counting on the water to take him back upwards. Instead he fell flat on the side of her inner thigh, spread eagle against her supple leg flesh. Did his idea fail?

Luckily not. A big trickle of water ran back up the thick leg and pulled Mark up with it. It splashed into Jen's crotch, giving Mark a facefull of her wet pussy. The current dragged him along her pink lips and for a second he feared it was about to swallow him. Fortunately the water kept going and he was pulled over her mons and along her smooth stomach.

Two massive shadows cast down on him from above and when he looked up he spotted two enormous soapy tits. He was heading right for them! He tried to aim himself between the two hills but it was no use. The water chose where he was going. Helpless, Mark braced for impact. With a poof he was thrown into the soapy bubbles and collided with her left underboob. The warm breast enveloped him in a comforting softness. It wasn't like her ass, which was heavy and crushing. This giant girl's boob was gentle and was comfy enough to fall asleep in.

Mark couldn't relax though. He was still under the torrent of shower water and about to drown. Almost reluctantly, he kicked off the huge boob and let the sudsy water take him away. It wrapped around the girl's ample chest and launched Mark from her collarbone. He went soaring into the airborne stream of droplets. Before they brought him to the shower head he swam free and was flung into the air. With this act, his daring escape was nearly complete, and the minuscule boy flew toward the shower curtain. Grabbing on, Mark let out a sigh of relief.

Once again everything had gone according to plan. Now all he had to do was slowly climb down the shower curtain and make his way to the floor. Then he would be safe from the giant girl that had accidentally been tormenting him all day. He didn't blame her, but at this point he wanted nothing more to do with her.

Slowly descending to the ground Mark was thinking of how to get home. Suddenly the sexy giantess stepped out of the shower, absentmindedly whipping the shower curtain open. Her actions flung Mark into the air once more until he landed on some soft stuffy cloth. Mark looked around, battered and confused, trying to identify where he was. His eyes told him he was in a pink cloth and his hand told him it was still warm. It was his nose that told him where he was, the familiar scent of the girl's ass was recognized instantly. He landed in her panties!

Two giant thundering legs were quickly approaching. Looking up, the nightmarish plump booty wobbled above him. It was still dry, he was now at the moment before she had entered the shower. It was also now where she was at her dirtiest. If Mark didn't get out of these panties right away he would be going back to that horrible ass. Then Jen would go back to sleep and he would be stuck inside her inverse-farting butt all night. It was the last thing he wanted. Did Mark escape the panties or was he pulled back into Jen's flesh?

Jen eyes slowly opened as she woke up to the sounds of birds chirping. She had just had a long pleasant sleep and felt ready to start the day. Sitting up on the edge of her bed, she could feel her guts start to awaken. The groggy girl ripped a massive loud fart into her mattress.

"Hah..." she sighed with relief. "That felt good."

Jen didn't mind cutting one loose like that when no one was around. It was embarrassing in public, but at home the smell of her own brand didn't bother her much. Her armpits were another story. She lifted an arm up and could smell the pungent caked-in sweat from the previous day.

"Hmm, no good. Time for a shower." she said. With that, she was up.

----

Back in Mark's reversed time he was standing in Jen's panties, quivering in fear under the gigantic butt that was standing over him. Within a few seconds should would pull up the dirty panties and pull him back in her ass.

"I didn't see this coming! Can I make it out of here? Do I have enough time?! If I jump off the panties when she's pulling them up will I fall to my death?"

He was overthinking it. Too scared to actually take any action, Mark just stood there and let the girl put on her undergarment. The cloth elevator zoomed up her delicious legs, taking the tiny boy with them. The daunting ass grew bigger and bigger in his view but he couldn't look away. Twin buns filled his vision until he was plunged between them, thrown yet again into darkness.

Her panties returned to their previous state, wedged far up her butt. After a long night's sleep her ass had devoured those panties like a hungry beast. Mark was lodged in the center of her thick cheeks, surrounded by tons of flesh on either side. They rolled up and down as the giant girl walked backwards to her bedroom, grinding the boy into nothingness. With every step she made her plump butt wobbled, crushing Mark inside while he cursed in pain.

"Dammit! How could this happen! I planned out everything! I was out! OH GOD WHAT IS THAT?!"

His nostrils flared up as her panties began to smell. The stench of her ass was awful! Then he felt a quick rush of vertigo followed by the immense butt flesh collapsing onto his small form. She had sat down on her bed. A small rumble built up into a raging storm around him. Gusts of heavy smell emerged from the mattress and flew in between her butt cheeks as the ass unripped its massive fart. Rolling thunderous waves of gas made her twin cheeks vibrate on the bed, searing blasts of flatus concentrated on Mark's spot. Her ass began to suck him up like before, but not before her giant cheeks had finished chewing him like a piece of gum. The sound of her inverse release was horrifying, it drowned out the tiny boy's screams with ease. Finally her ass calmed down and Mark was left farther up her butt crack, much closer to her rancid hole.

Then... silence. The giantess had laid down and returned to her state of sleep and things for Mark got real boring, real quick. He was flattened under the pressure of the girl's ass halves and was unable to escape, let alone move. Time crawled by in reverse slowly, all he could do was lie there and breath in the smell of her butt flesh. It wasn't great, but at this point he was used to worse.

Hours went by. Jen was lying on her side, her cute butt cheeks looked like two pale hamburger buns. Deep inside, sandwiched between them was Mark, the "meat" of this perverse burger. He reflected on his situation. Even though he was in a shitty situation, at least the girl he was with was hot. It could have been much worse. An old fat hag could have walked into that unisex bathroom, or even worse... a man. Mark shuddered at that though.

Jen shuddered too, only it was her butt that shuddered. Another deafening blast of gas pummeled Mark's body, sending him further inside the beastly booty. The sideways rumps gobbled him up with the fart and brought him deeper with the stink. Unknown to the both of them, Jen was prone to night farts, and would expel lots of gas while she slumbered.

Throughout the night that was what he had to deal with. Hours of nothing and then roaring chaotic farts. Sometimes they were loud and pulled him in deep. Other times she had rolled on her back and the weight of her cheeks held him in place. One time an especially big fart woke her up. She sat up still half-asleep, cutely asking "Anyone there?" while Mark yelled and screamed inside her butt. Hearing none of it, she went back to sleep.

The giantess slept on calmly, unaware that her ass was eating a boy yet again. Each bout of gas pulled him in a bit more. It was like the monstrous butt was giving him a taste test before swallowing him whole. Licks of gas rolled him around in the beasts "mouth" savoring his body until it felt like the time was right. After each fart went away Mark could hear the bowels gurgle as if the ass was getting hungrier.

Finally one of her butt blasts had brought him to his destination, her anus. The puckered hole eagerly gulped the last of her fart and pulled Mark with it, giving him a light kiss on the face. Mark recoiled away from the nasty asshole, spitting the taste of it out of his mouth. The wrinkly maw quivered and flexed, like it could detect his presence. Mark tried to stay away from it as much as possible, the heat coming off of it was enough to make him sweat. The only thing was he had no place to run to. Down in the core of this girl's ass crack it was just him and the slimy gross anus.

Another agonizing hour later is when it happened. Mark heard a muffled rush of wind from outside the colossal walls of butt flesh behind him. The pocket of air wormed through her bubbly cheeks and converged at a single point in her crack. The air pocket burst open on Mark like a shotgun blast, all the heat and smell engulfed him at once. The greedy anus convulsed and spread open to let the fart through and suck Mark inside.

Desperately he clutched the rim of the vibrating shithole, using all his strength to stop it from sucking him inside and eating him. The anus shrank around his head, still farting while it suckled on his skull. Mark shouted in pain as the rumbling wrinkles tried to rip his head from his neck. It wasn't open wide enough to get a grip on his shoulders. Mark's lower body was squirming and dangling as he tried to wrench himself loose. The hot fart popped inside and the butthole squeezed shut on his head. A slimy anus wrinkle had wedged inside Mark's mouth and now he couldn't breathe. Terrified, the boy screamed for help.

That scream was important. The vibrations sent tingles of pleasure back to Jen's subconscious mind and her body. Mark didn't realize that his cries were turning her on. He had forgot how his actions had an effect on the past. Since time was going backwards, if he turned on the giant girl now she would need a reason for feeling pleasure in the past. Mark pulled his mouth out from the asshole but the rest of his head was still stuck inside. Not that it mattered, it was too late. His careless actions had created a new event on his timeline!

----

Jen relaxed and put her panties back on. Finishing masturbating in bed for the night, she rested her head on the pillow and let her tingles of pleasure put her back to sleep.

----

Mark would slowly learn of what was coming. The ass would begin to get hotter around him. Her blood would slowly start pumping faster, creating loud thumps in her puckered anus. The erotic hole would start to spasm and loosen, letting Mark's head free. He could see and feel the dried sweat on her body turn into liquid again, coating his body in juices. Beyond that he couldn't see it, but her whole body was beginning to glisten in sweat. Her nipples slowly stiffened and her heart raced. The girl's body was returning to a state of heightened arousal, one achieved by her own masturbation. And with the way her asshole was opening up it looked like that was the hole she used to cum.

A blinding surge of light came to Mark as the girl's panties were removed and her ass was spread. The shithole behind him drooled with lust as a blurry thing approached Mark from the outside world. It was ready to plunge him in a hell unlike he had ever seen. What was it?

The giant girl's hand gripped the shaft of the massive dildo as it made its way closer and closer to Mark's tiny body. The overbearing phallic object looked like it was the size of a train compared to him. Knees quivering in fear, Mark stepped backwards until he felt the wet spread asshole behind him. It was quivering as well, hot shitty breaths puffed from its gaping "mouth". Mark dared a look into it, the dark tunnel extended towards an endless slimy black chasm, one he remembered all too well.

Looking forward again, the humongous dildo was directly in front of him, leaving him with nowhere to run. He was finally piecing together what was happening. Since time itself was flowing backwards for everyone but him, the sticky dildo could only mean the end of the giant girl's masturbation. It was about to take an express trip up her ass and make her cum. Unfortunately for Mark, he had a boarding ticket.

Sure enough, the dildo struck him square in his gut and plunged inside the girl's ass. With a loud inverse pop and a SPLORCH, the satisfied hole sucked the dildo back inside without any assistance from the girl's hand. Mark was face down, spread eagle on the head of the dildo, and back to being shrouded in stuffy darkness. The heat was unreal as it had been during his first trip up the girl's bowels, and the smell was just as bad. All the farts that he had experienced while she was sleeping had been locked away inside this smelly dungeon of hers. It was hard to breathe them and the smell felt like it was sticking to his body.

Gradually the ass pulled the dildo back up the bowels. It slowly wormed through the throbbing hot walls, and Mark could feel the slobbering flesh pulling on his back. As it went the walls got hotter and more rambunctious. Her heartbeat increased and the internal rings of muscle would sometimes lightly spasm. Since Mark was experiencing life in reverse order it meant that the giantess was going to have a big orgasm first and then masturbate after it. The dildo was slurped up faster and faster, the heartbeat quickened and thumped so loud that it was maddening. The giant sex toy jerked and stopped as her hand grabbed onto it. Mark had arrived at his train station's stop: Cumming Bowels.

The hot muscles seized the dildo in a huge squeezing clench, holding both it and Mark tight. A disgusting SQUELCH brought the sticky walls away, but only momentarily before they pounded down on him again. The grip of her bowels were iron tight, crushing the boy while rubbing filthy shit-stained paste on his back. Another second of relief before more anal pounding. The groaning cavern contracted and relaxed repeatedly until it knocked Mark off the dildo.

"NOOOOOOOOOOOOOOOO!!!" he screamed, getting hot slime in his mouth.

A flurry of anal juices and frothy lube consumed him. He was thrown around the giant girl's cumming walls as her bowels chewed him up. A loud BOOM was heard and his world quaked. The throbbing flesh slammed down on him repeatedly, loving the feeling of his squirming body. SPLORCH! SQUOOSH! SPLOTCH! Mark was desperately squirming, trying to make his way back to the dildo. It was his only escape from this hell. He was making little to no ground, all his struggles were doing were arousing the giant woman more. A mortifying scream was heard from outside her ass, going in reverse. It was the call of her pleasure, and after it rang loud and clear the hot anal walls clenched down on him harder than ever before.

----

In Jen's timeflow she had been fucking her ass with the dildo for a while. It felt so amazing, she hadn't been this horny in a long time. She felt her orgasm building slowly until she was ready to reach climax. She got onto her back and quivered in anticipation. Her plentiful breasts heaved up and down with her chest. With a grunt she thrust the dildo hard and came. The tight walls squeezed around the big sex toy over and over.

"Yes! YES! YEESSS! OOOOOHHH GOOOOOOOOOOODDDD!!!!" she howled in delight.

Her ass spasmed and clutched the dildo tight. Feeling such pleasure in her ass was the best. She was glad to been born with such an amazing butt. She spanked it, letting her massive cheeks wobble erotically. Today felt better than usual, like there was something else other than a dildo inside her. A small warm ticklish feeling in her ass that made her extra horny.

Her hips shivered and her pussy spurted a small squirt of juice on her bed. She didn't care. She felt so satisfied and relaxed. Letting the dildo slowly slide out her ass felt great. It came out with a pop and she picked it up and put it on her beside table. Feeling tired, she put her panties back on and went to sleep.

----

Mark had the air knocked out of him, and when the walls retreated he had to heave in the musk from her stinky bowels. Things were still for a second until the dildo bulldozed him further up the shit tunnel. Again Mark screamed, the bumpy walls had more feces the deeper he went and they clutched him with more love too. Mark didn't want their love and he didn't want to feel their hot slimy touch either. The dildo retreated as fast as it had plunged him in, and the world suddenly turned. The giant girl had got to her knees and lifted her ass high and pointing upwards. Her face was down on her pillows moaning as she begun to jackhammer her ass with the dildo.

Mark only had a second before the dildo came back, driving him deeper inside. It violently pushed him over and over until his back was pinned against a hard fleshy wall. It was the corner of Jen's large intestine and her favourite place to tickle herself with her dildo. She pounded him again and again with the massive sex toy, screaming while she did so. The girl was in a state of pure bliss, unaware of the tortures she was putting the tiny boy through. He yelled in pain, uselessly holding his arms out to stop the oncoming phallic object. Sometimes it crushed his head, others it smashed his dick. Horrible SPLOTCH noises came with the dildo, and each it thrust he was splashed with a wave of lube and butt slime.

After a few minutes it started to hold back. With each push the dildo got farther and farther away from Mark, leaving him alone in the heavy bowels. Fear came over him as he listened to it retreat back to the outside world.

He yelled. "WAIT! COME BAAAACK! DON'T LEAVE ME IN HERE!" but the inanimate sex toy didn't listen.

As the giant girl went back to the beginning of her masturbation process it meant she was slowly pushing the dildo less and less up her butt until it wasn't even inside at all. Soon enough she was using a finger to tickle her anus until she unlubed the dildo and placed it back wherever it came from. Mark was left deep inside her hot ass, battered and fucked and left to rot like a piece of shit.

How could he be here again? He had planned and escaped so perfectly. It was like escaping prison, only to dig a tunnel that led to another prison. Was he really doomed to be inside this girl's ass forever? Was it his fate? Like he had somehow defied the universe and now it was punishing him?

There was only one answer and it came in the form of a rancid smelly hot fart. Jen's ass had laid down a big one, and now it was rushing back inside her. Horrifying gusts of burning gas swept Mark away. He felt the familiar feeling of being sucked back up this shitty anal tunnel. The walls vibrated and spewed their thick hot gases inside. Mark choked on the thick fart, the misty smell was all around him. The anus gave a big gulp and finished pumping in the hot fart, leaving Mark stranded. 

----

Before the intense buttfucking, Jen was calmly on her bed reading a book. A small gurgle came from her gut and when she pushed, her ass let out a rumbling fart. She giggled at the size of her release and smirked at the sensation. It felt kind of nice when her anus fluttered like that, it stirred something inside her. When she thought about it, she hadn't really given her ass much attention lately.

Closing her book, Jen leaned over to her bedside table drawer to grab her favourite dildo and some lube.

----

Mark was terrifyingly deep inside her ass and doomed. Doomed to spend eternity within the sexy ass of a hot young girl. Doomed to stay under the curse of reverse time. No matter how he escaped it felt like he would always find a way back now. Maybe it was best to just drown in shit and let it kill him.

It was in the depths of his despair that he saw a faint glimmering blue light. He weakly crawled toward the glow until he saw what it was. Lodged between the puffy bowel walls and a small hunk of crap was the device. Mark thought he was delirious from the overbearing stench but when he touched it he realized it was the real thing. He looked at it half expecting it to turn to dust. He couldn't believe he found it, his so called "lucky charm" that had brought him to this hell. Twice.

He was so mad he had the urge to smash it right then and there. But more than anything he wanted to get out of this. Was he screwed? Would it even work now?

Without hesitation Mark hit the activation button on the device. Nothing happened. The blue display screen gave him a simple and blunt message: ERROR. Mark's face twisted in dismay. Again and again he hammered the button, not ready to believe his last chance of survival was broken. The blue screen repeated the same message for every attempt. ERROR ERROR ERROR ERROR ERROR ERROR ERROR ERROR ERROR ERROR ERROR ERROR ERROR ...ERROR.

Mark threw the device far down the tunnel, frustrated and sobbing. It landed face-down in another pile of excrement, the disgusting mess covered the display returning the boy to darkness. Mark was sick of all this. Every breath he took made him want to gag. He was so deep inside the cavernous bowels that the air tasted hot, like the inside of a sauna. Distant gurgles reminded him where he was, with any sudden noise or movement he braced himself for another burst of gas.

For now, the giantess wasn't moving. If he wanted to live he needed to back himself out of her gigantic butt, before he suffocated or starved. If anything he felt like exhaustion would take him first. The pressure combined with constant radiating heat was sucking out all his energy. Slowly he began to crawl backward down the girl's shitty tube again. Every step hurt his joints and made his arms buckle but he kept telling himself that the exit was a few steps away.

----

Jen was just glad it was finally Friday night. School felt like it had gone on forever this week and right now she was aching for some R&R. There wasn't much food left in the house and the only appealing thing she found in the fridge was a couple leftover slices of pizza. They were a few days old but she didn't care, her stomach could deal with that tomorrow.

After downing her microwaved meal she gave a soft burp and patted her belly. For now it was calm but Saturday would be another story. She sauntered her big juicy butt over to the living room and plopped it on the couch. Reading some magazines, she saw a few outfits that she planned to hunt for at the mall tomorrow. There was a pair of leggings that looked like they would really accentuate her ass. Looking down at her perfectly shaped butt, she smiled at how sexy it was.

"You're gonna make the boys go crazy over you. You're gonna eat them ALIVE out there" she boasted to her ass confidently.

With her malls plans for Saturday all ready, she made her way to the bedroom and laid in bed to read her novel. Relaxing in that same spot for a few hours, she unknowingly gave Mark the time he needed to crawl back down her poop chute.

----

The musky gas was getting to him. It's like his lungs were clogging up with the girl's crap. When he coughed he was pretty sure some shit came out but there was no way to tell. Everything in here was coated in feces or slimy anal mucus. His back, legs, arms, and hair were all weighed down by the revolting goo, and it only made his journey harder. More than a dozen times the sticky juices caused him to fall flat on his stomach, coming up to his eyebrows in unspeakable warm gunk.

Hours passed to the point where Mark recognized time as meaningless. Backwards or forwards, it didn't matter. Every second felt like the same hellish torture over and over. There was no progress anymore. Just shitty smells, shitty tastes, and wet, emanating heat. Delirious and nearly out of energy, Mark weakly trudged through the bowels like a zombie.

All that changed however when a blinding light pierced its way into the intestine. Mark squinted, looking back to find that the girl's anal mouth was miraculously opening! Cool air made its way into the ass, cutting into the humidity and rejuvenating Mark's tired body and soul. Now that he could see the path, he found that he was only a short distance from the anus. He was so close! Mark picked up his pace, he was rushing towards the exit filled with determination.

"I'm almost there! I'm going to make it out!" he cheered.

He was at the colon and about to step his legs into the giant rubbery anus when it happened. A large object appeared in front of the hole and obscured most of the incoming light. Mark looked back again only to see a huge turd approaching him with great speed. The giant girl was on the toilet! Her ass was taking a shit in reverse and was about to suck up all her poop!

"FUCK FUCK FUCK FUCK FUUUUUUUUUUUUUUCCCCKKK!!!" Mark screamed before being engulfed in the sticky mass of waste.

It had been a long time since Jen had taken a dump so this was a big one. The first pieces to meet Mark were relatively small compared to the rest, as they were the last bits to come out. Foolishly the boy tried to push his way past the poop and force his way out the asshole. The oncoming shit knocked him backwards and he fell down, only to be squeezed by the wrinkly asshole. The monstrous hole flexed repeatedly on his poor body, sloppily chewing him with the slimy wad of crap. In Jen's time she was calmly winking her butthole over and over to get out this last piece of poop. In Mark's time however, the giant anus was sucking the shit back in, all the while gnawing on his shrunken body.

The massive pucker made gross noises while it chewed on Mark and the shit. Wet smacking sounds filled Mark's ears along with the horrifying THUMP THUMP THUMP for every time the hole collapsed down on him. It was like a giant mouth was devouring him, and sure enough it began to swallow him back down. Mark was about to be carried away with the poop until he wrenched himself free from its sticky grip. He fell down once more and was only halfway through lifting himself back up when a second poop clogged the exit hole.

The anus started to repeat the chewing process again, mashing Mark into the fresh pile of crap. This time the disgusting waste wrapped around his body and the powerful butthole compressed the poop down on him. Soon he was encased in the shit, unable to move his arms or legs, with only his head sticking out. With one nasty SQUELCH the sphincter gave a modest gulp, sending him on his way. Mark screamed at the top of his lungs, his cries echoing off the walls of the girl's shitting bowels.

His head was forced to watch as another, much bigger turd wormed its way inside the girl. The shithole didn't need to flex or chew her poop anymore, the next oncoming turds were big generous logs that had been released with ease. The girthy shit shot up the asshole and went straight for Mark's trapped body. The clutching bowel walls eased the log along, using their muscles to swallow it like a hot steamy throat would. Mark yelled for help up until the moment the shit collided with him, filling his mouth with horrible burning crap. The huge turd merged with the previous piece of poop that had captured Mark, completely encasing him in one big mass of shit.

Jen's gaping anus continued to gorge on the enormous smelly logs, sucking them inside as easily as they had come out. Between the series of turds she had a few farts as well. Hot blaring bouts of gas exploded back inside her anus, swirling through her bowels. The rancid air warmed up the shitty tunnel and multiplied the stench within. The space inside her bowels was rapidly filling, becoming more and more cramped with each new turd that came.

Deep deep inside, Mark was compacted under the weight of dozens of feces. He had nowhere to run to and nothing to breathe. His last chance of escape had failed and now he was going to die. Throughout his life he thought he would have a more dignified death, but right now he was panicking and scared beyond comprehension. Nothing but fear ran through his mind as he struggled, his trapped body slowly choked on chunks of shit. The last moments of his life were spent weakly wriggling around, entombed in a giant girl's shit who didn't even know he was dying inside her ass to begin with. Her anus slowly closed shut, encasing the boy within forever.

----

Jen burst from her front door, just returning from her day at school. She made a mad dash straight to the washroom and locked the door. The hurried girl had to poop NOW. Finally pressing her naked wide hips on the toilet seat, she let out a sigh of relief and unloaded into the bowl. Her ass released its enormous payload along with some boisterous farts. Jen knew she shouldn't have waited that long to poop but the feeling of letting it all out at once was amazing.

She smiled in relief as her backdoor sputtered out a few final lumps of shit. For a moment she thought she felt her anus squeezing on something else besides the poop caught in her asshole but it was probably just a piece of corn or something. She had no idea that there was a tiny shrunken boy in her poop and her ass had just sentenced him to death. Completely carefree, Jen flushed her mess and went to the kitchen to make some dinner.

----

Mark's disappearance was a mystery. No one knew where he went after that coming Saturday and after a few years his family presumed he was dead. His corpse was sucked back up through Jen's digestive system and completely disassembled into unrecognizable goop. After that it was absorbed by her health body leaving no trace that he had ever existed at all. The device, Mark's "lucky charm", and the only proof left of his horrifying journey, stayed lodged inside Jen's bowels for many years until it too decayed into nothing.