"...Okay."

He couldn't deny Sarah's request. Not only was having his crush sit on him with her giant ass his greatest fantasy, but from what she had just told him, it was hers as well. His response made her grin, and her eyes gave him a sexy "come hither" look. Mark walked a few steps towards his goddess when suddenly she started to get up, shaking the whole bed. Turning around, the gorgeous teen presented Mark with her full leggings-covered backside, which was just as enormous as ever. Sarah's ass was a work of art, a flawlessly sculpted pair of cheeks that were both plump and tight looking at the same time. Her wide ass complimented her otherwise petite body perfectly, creating the most appealing view ever to be seen as she arched her back.

Bending her knees, Sarah lowered her magnificent booty directly above Mark's body, casting a giant heart-shaped shadow over him. He knew how insanely heavy her ass was compared to him, yet he was still eagerly anticipating being flattened by it. The soft plump masses of her butt cheeks looked inviting, like his tiny form belonged between them. Sarah's hands tugged the side of her leggings and panties, slowly peeling them off as she began to talk dirty. With every word she revealed another inch of juicy skin to Mark, teasing him to the sight of her beautiful luscious ass flesh.

"Here it is Mark... my giant sexy ass that you like so much. I can feel another fart coming, slowly filling up my butt. It's going to be a big one, a nice, hot, noisy one. And you know what? I want you to be right in the middle of it. I want to sit on top of your tiny, sexy body and blast you with my fart. I want to feel you between my ass cheeks as I let... it.... rip~."

Hearing her voice say such dirty words was extremely erotic. The friendly Sarah he knew from school was showing him a side of herself that she hadn't shown anyone before. As she pulled her leggings and panties all the way off her ass, the crotch of her underwear stuck to her skin for a second. It then came off too, stretching a beautiful shimmering line of juices from her slit. Her whole pussy was dripping wet with arousal, it was obvious that she was every bit as into this as Mark was.

Without hesitation the giant girl lowered her magnificent butt on top of him. The huge wobbling cheeks blocked out everything else in his vision, so all he could see was Sarah's smooth skin and the dark crack leading between her butt cheeks. Roughly her ass pushed his tiny body down on the bedspread, pinning him to the soft sheets where she would sit. Just before completely crushing him under her weight, she slowly spread her butt apart with both hands... displaying to him her juicy, sweat-coated ass crack, overwhelming the tiny man's senses. Mark took a whiff, a single smell of her delicious raunchy ass scent before the massive impact of her body weight came bearing down on him.

Sarah's butt crack was still steamy with the smell of ass sweat from earlier, even after being wiped in the bathroom. The dizzying scent of female pheromones hit Mark like a crashing wave, drowning his thoughts in a sexual fever. Sarah's glorious round globes were hugging him in a warm smelly embrace, squeezing his body tight enough for his skin to fuse into hers. Every breath was filled with her addictive odors, every inch of his body caressed by her pillowy buttocks like he had died and gone to heaven. Mark had reached a state of euphoria. This one moment here was all he could have ever dreamed of. His high-school crush was sitting on top of him, squeezing him between her lovely butt cheeks and wrapping him in her scent. Not only that, but unlike before she was actually doing it willingly. This girl wanted him snuggled up in her butt... and she wasn't about to stop it there.

Sarah started to gyrate her hips into the bed, rubbing her massive booty all over Mark. She wiggled from side to side, drawing the boy deeper between her ass halves and closer to her delicious center. Mark felt the temperature of her soft skin get warmer the further her went, like he was being pulled into a marshmallow roasting over a campfire. The girl teased him some more as she wiggled her butt.

"Do you like this Mark? Does it feel good under my ass? I want you nice and deep in there... right up against my asshole. Oh! There, can you feel it? My giant hole pressing against your head? It's almost ready to fart on you, to let it all out on your face. I want you to smell it all."

She was right, Mark's body had been wedged all the way up her ass crack and now he was squashed directly against her asshole. If the rubbery tense skin wasn't already unmistakable, the stench was. Sarah's anus was still drenched in the smell of her past farts and latent shit. Mark didn't even have to lean his neck forward to nuzzle against it, this time the anus came pressing down on him. Sarah pushed playfully with her butt muscles, flexing her huge asshole so that it planted itself on Mark's small frame. He was completely enveloped in her oily wrinkles, treated to a full frontal massage of the girl's anal orifice. The giant hole undulated and flexed on his head, sensually smearing tasty sweat and filth against his skin.

Finally a loud gurgle stirred through her body. The rumblings of her bowels vibrated against his body as her fart built in pressure. Her anus winked against his head, clenching slightly around his face to hold the intestinal air back. The giant wrinkles squeezed his mouth like a suction cup for a moment before separating, leaving a line of anal drool connecting the two. Sarah's entire ass purred erotically, her shithole was twitching right in front of his face, ready to pour her hot stinky lust all over him. Mark was panting with excitement, he gazed up at the faint outline of her puckering anus as he heard her voice.

"I think I'm ready now. It feels like a big one, I hope you can handle this... nnnngh!"

Her sticky shithole widened in front of his face releasing a tremendous gust of noxious gases. With no reason to hold back anymore, Sarah let her giant fart erupt wildly. The incredible shockwaves pounded Mark into the bed, and made the whole mattress rumble under her sexy butt. Beneath her cheeks he was treated to a whirlwind of her delicious scent, hot rancid fumes billowing forth from the darkest depths of her bowels. It was hot and messy, punctuated all the better by the noise of her juicy trumpeting anus. Its hot rubbery wrinkles vibrated together, spraying tasty droplets of sweat and anal fluid all over Mark's visage. The fart assaulted his nostrils making them sting with its ferocious odor, but he inhaled it deeply all the same. He was totally addicted to Sarah's gas, and wanted to huff down every bit of it.

This was bliss to him, heaven in its purest form. He wanted to stay under Sarah's ass forever, travel between her cheeks every day and have her fart on him, just like this. Her anal scent was just so sexy, he couldn't help himself. The hot and thick meaty gas, the distinct harsh taste and smell of her farts, it drove his lust into a frenzy every time. His eyes rolled back a little as he breathed in her smell, drool came from his mouth as he was surrounded by the fart's warm embrace. There was something about knowing Sarah was into this, something different about her consensually farting on him that made it ten times hotter than it was before. Just knowing that she was also getting off on this amplified his own arousal. Mark inhaled the burning scent into the back of his throat and held it in his lungs, becoming dizzy from its intensity.

Sarah's shoulders dropped as the fart left her butt. The feeling of warmth spread throughout the cloth of her bed sheets, turning the fabric landscape under her ass into a wasteland of burning shit fumes. A sense of relief was felt through her bowels after she had let it all out, but then she snapped right back to reality. Mark felt the enormous weight of her body spring off him and was hit with light again. Sarah snatched him up in her hand and brought him back to her face to see if he was alright.

"Mark are you okay?! Was that too much?! I didn't realize it would be THAT big, sorry!"

She broke her sexy playful voice for a moment and had gone back to normal Sarah. She was genuinely worried that her ass had been too much for him, that last fart was a rather big one. Mark was still in a daze, but a happy one. He had a dopey but incredibly aroused look on his face and his dick was standing rock solid. He blinked a couple times before speaking.

"Oh my god that was so amazing Sarah. Your farts smell so good I want smell more of them from your perfect ass." the boy rambled on.

Sarah blushed red and smirked.

"Well then, it looks like you're just as wild as I am..." she teased.

Giving her horny classmate his wish, she lowered him back down to where he came from. Mark's excitement rose back up as her gigantic ass cheeks eclipsed his tiny body once again. Inside her crack, Sarah's butthole was twitching, ready for round two.

"Remember what you said you did in class today?" she asked him. "How you told me you stuck your face right up in the crevices of my butthole and made out with it? How much you loved the way my anus clenched on your tongue? How would you like to make out with it for real?"

Mark stared into the giant lusty asshole waiting for him. It was wet, drooling a line of anal mucus and puckering with arousal.

"This time I promise it'll be gassy~." she added.