“Oh my God, bro! You totally shrank as you blew your load in me!” Jackie deduced as she sat on top of him. She could feel his cock getting softer inside of her, it still sporadically spurting the final few droplets of his cum into her vagina.

Scott couldn’t control his tears as he continued to turn away from his huge sister, trying to process what had just happened. Jackie sighed unsympathetically, “Oh stop that, midget boy! You just got fucked by the hottest girl in school - and those are your words, not mine!” She shrugged, “So what if I’m your stepsister, it’s not like we’re related. You should be kissing my fat ass for what I just did for you… to you…”

“P-Please. I’m just so cold,” Scott said, shaking as he was still pinned beneath her, “I… I just need a break. I need sleep!”

“Sleep?” Jackie asked, laughing at the state of him, “”Ha! Not gonna happen, squirt! Not after what just happened. God, look how small you just got! You’ve gotta be a good amount under four feet now.”

Climbing off of him, she watched as Scott’s limp dick flopped out of her with a puddle of their cum onto his stomach. Admiring what she had done as he lay there, she slipped her bikini back over her vagina and patted it lightly in place. “Come on!” she said, reaching down to grab him.

“Get off of me!” Scott screamed, slapping her hands away as she tried to slip her hands beneath his arms to lift him.

“Stop it, don’t make me spank you!” Jackie shouted, grabbing him more aggressively as he froze from fear. He really didn’t want her to hit him again, unsure of how much more he could take.

Now carrying Scott without resistance, Jackie brought him over to the standing mirror. As she placed him down beside her, she began to compare their differing sizes.

Scott dared not look at her, but he couldn’t help but spare a glance. As he peeked out from behind his hands, he was met by an unholy sight - Jackie’s bulging cameltoe at perfect chin height.

Turning her ass so it was directly in Scott’s face, she demanded, “Kiss it!” As Scott reluctantly pressed his lips up against her cheek, she allowed a subtle moan to escape her lips. Grabbing his shoulders, she brought him closer so his face was directly in front of her pussy. “Now the front, dweeb!” she demanded.

Scott squirmed in her grasp, trying his best to turn away. “What, you’re too good for me?” she asked, pulling her bikini to one side once more, and displaying her healthy bush and thick pussy lips. Her juices oozed down her leg as she watched him slowly inch closer, hesitating all the while. She bit her lip in anticipation.

Panicking, Scott shook himself from her grasp and turned to run. He made it barely even a couple metres towards the door before Jackie was directly behind him and wrapping her hands around him. Scott screamed out, arms flailing, as she dragged him over towards the bed.

“What do you think you’re doing?! Running from me?” she shouted, as if she were berating her naughty child.

Scott’s eyes were streaming with tears as he desperately tried to escape from her grasp. “Please! Let me go!” he begged, squirming away from her and making another dash for the door. This time reaching it, he pulled at the handle with both hands and pulled it open.

The door opened only a slither before Jackie quickly closed the gap and slammed it shut in his face. Scott stumbled back, dazed by the loud bang directly in front of him. “You can’t run from me! How dare you even try?!” she screamed as she grabbed him once more, her vagina exposed with her bikini still pulled to one side.

Dragging Scott once more over to the bed, she bent him over the side of it. With him kicking and screaming, as she held him, she brought her hand high into the air. With no warning, she began to spank his ass repeatedly - creating a huge, red blodge on his ass almost immediately. Scott howled in pain, his whole body pulsating from the agony.

“Aw baby, don’t cry too much! We just need to toughen you up!” Jackie declared, her hand connecting to his ass slightly harder to emphasise each word. Meanwhile, Scott can feel the twinge in his cock, it slowly growing in length.

Finally relenting, she turned him around and was met with his twitching cock in her face. “Oh my God. You’re a sick fuck, you know that?” she laughed, “You’re getting hard at me spanking you, and you’re crying at the same time!”

Scott sniffled quietly in her grasp, trying to hold back his sobbing. His face flushed red from embarrassment, his mind desperately searched for a way to not be aroused at this situation. He was so weak, and disgusting. How had things come to this?

“You know, squirt, it doesn’t have to be all bad.” Jackie explained, “If you just quit fighting it and let it happen, you can see that not all of you is complaining.” Releasing her grip, she stood him up on the bed before her and leaned in towards his crotch.

Scott struggled to stifle a moan as she pursed her lips and wrapped them around his dick. He could barely stand as she began to suck, swirling her tongue all around his erect shaft and gently brushing the backs of her knuckles against his tiny testicles.

His eyes rolled into the back of his head as she sucked the life from him. Placing his hands upon her shoulders, he tried to support himself, his legs becoming weaker as she brought him closer to orgasm. He couldn't even think straight, the pleasure she was causing rippling up his spine in waves.

And Jackie was on a mission. If she fucked him, and he shrunk when he ejaculated… Then maybe she could make him shrink on demand, any time he came for her. She could feel his cock getting harder in her mouth, a strong signal that he would cum any time now.

Scott tried not to enjoy it, he tried whatever he could to stop her. But there was nothing he could do. She sucked and sucked, pulling him in close to her as she easily took his full length into her mouth. There was no telling how small he’d get, but this was for science.

*******************************************

Jackie lightly stroked her fingers through his hair as he lay upon her chest, his head cushioned between her tits. “God bro, I didn’t know you had it in you. Five times in under an hour!” she said, sinking deeper into the sofa to get comfortable, “If I had known you had the hots for me so bad, I may have just given you a pity hand job or something. You’re quite the perv!”

Burrowing himself deeper between her tits from shame, Scott stuttered back, “I… I d-don’t. You’re my… my step s-si...“

“Bullshit!” Jackie countered, “Your wimpy ass has the hots for little sis. You must be just a little over three feet tall now? Still, I was kinda hoping you’d be smaller after all those blowjobs...  Guess it’s not an exact science or something.”

Looking up at the ceiling as she continued to stroke him, she wondered, “Maybe it’s the size of your load, or maybe it’s just random? I dunno… I guess we’ll just have to try a few things later.”

Scott began to writhe in panic, causing Jackie to hold him tighter against her. “N-no!” he begged, “I… I’m too sore. And w…”

Jackie pressed her tits together around his head, engulfing it entirely in her soft, bulbous flesh. His cries were too faint to hear as she spoke, “What did I say about speaking without permission?” She held him there for a short while, to emphasise her point to him that she chose when he spoke, before finally releasing him. He silently gasped in air, finally free of her vice.

“Yeah that reminds me,” Jackie began, “This whole little sis, big bro thing just isn’t gonna work, obviously! You’re little bro, and I’m big sis now, got it?”

“Y… Yes, Jackie.” Scott uttered quietly.

With a more affectionate tone, she replied, “Good boy,” as she went back to calmly stroking his hair. Reaching over to the TV remote, she turned the news on. Slowly tracing her hand down his body, she toyed with his raw, sensitive dick playfully instead.

BREAKING NEWS. Congress and Vice President Hope have invoked the 25th amendment, declaring President Klein unfit to lead. This happened just one week after news that President Klein tested positive for the Y-Strain. We go now, live, to President Hope, with an important message from the White House.

Standing now in the Oval Office, President Hope shuffled through her notes as the cameras cut to her. “Fellow Americans, it comes to us with great sadness to declare that President Klein will no longer be able to lead this great nation.” she began, her tone calm and direct, “His condition, infected with the virus that continues to plague so many of our loved ones, has worsened significantly. We’re all wishing him a speedy recovery, in these troublesome times.”

She shuffled her papers once more, sliding the first page to the back. “To limit the spread of the virus, we are imposing an indefinite ban on all air travel. Scientists are working day and night to find out more information about how the virus spreads, how it mutates, and how it affects the body. But our knowledge on the matter is still very limited.” she explained.

Scott’s eyes widened as his gaze remained glued to the TV screen, terrified at what he was hearing. His mouth fell open, and his heart rate increased drastically. He dared not speak, nor move. He wanted to hear all of this. He felt Jackie shifting beneath him, and he could sense her smarmy grin directly above him. She knew what this meant for them, and it was only good news… For her, at least.

As the president finished up her speech and asked for questions, a reporter called out, “Various news outlets have recently reported a correlation between symptom progression and sexual activity... Can you confirm?”

Packing away her things into her briefcase, President Hope stepped back up to the podium for a moment. “The CDC is working day and night to research the virus. However, early data does not support the rumored link with sexual activity. Our priority right now is to stop the spread. We do not advise you to make any rash decisions based on unfounded information, but rather wait for official guidance. Thank you.” President Hope replied, her words carefully chosen and well executed.

As the news bulletin ended, Jackie’s phone lit up and buzzed aggressively on the side of the sofa. Reaching over, she tilted the screen so they could see who it was - it was her Mom. Lifting it to her ear, she answered, “Hey Mom... Yeah we just saw on TV, what horrible news… Calm down Mom, he’s fine.” She looked down at him, as he looked back up at her, her eyes piercing into him threateningly.

“Mom, you’re not gonna wanna hear this… But Scott’s got it… I dunno, maybe a little over three feet?... I’m taking good care of him… The hospital? Mom they’re at full capacity right now, he’s safer here with me… Drive? That’s like two thousand miles from here, are you crazy? You can’t afford a rental for that kind of drive…” Jackie ranted, trying to calm her Mom down and avoid her making any decisions that might have led to her coming home sooner.

“Listen, you need to just focus on your job. I’m already taking real good care of him, you have nothing to worry about.” Jackie explained, her authoritative tone calming for her Mother but horrifying for Scott. He considered shouting up for help, but the fear in him kept him quiet for now. She continued, “Yes, I know they get cold when they’re small. I’ll keep him warm, I promise! We can move him to my room in case of emergency.”

Hearing Jackie’s proposal, Scott’s eyes widened in terror. He screamed out to the phone, “Mom! Mmm…” Jackie quickly cut him off, clasping her hand over his mouth and pulling him in close between her huge tits.

“What, that? Oh that was nothing, just the TV... No, no, he’s sleeping right now, I don’t wanna wake him. He needs his rest… Sure thing, I’ll give him a hug and kiss just from you. Bye, be safe!” Jackie concluded, finishing up the conversation satisfied with how it had gone. Everything was coming together nicely.