“Turn around girl,” the tall man says, spinning a finger in command. “I wanna get at that beautiful booty of yours.”
You shift your weight as Kat’s panties, forcing her to turn in place. You punctuate the movement by jutting her ass upward, forcing her to curve her spine provocatively.
“Yeah! All right, this girl knows how to party,” the man calls, and gives her butt a smack to the applause of the crowd. “Ow! Don’t do that, my butt is very sensitive!” Kat whines. “My body is moving on its own, I don’t want this!”
“That’s okay! Let the passion move you,” the man purrs, misunderstanding her protest. He leans in close, placing his hands on her hips as he gets a closer look. “Damn, where the hell did you get an ass like this?”
“It’s not my AAAHHHHHH!...” she moans suddenly. You’ve taken advantage of the man examining Kat’s behind and you cause it to surge outwards in growth, burying his face between her plump cheeks.
The crowd surrounding you hoots, nobody apparently catching on. Kat blushes bright red and tries to escape, however her increased topheaviness topples her to the ground. She lands squarely on her oversized breasts, making them squash, emphasizing their size as her ass lifts higher into the air. The crowd cheers again.
Hair slightly mussed from having his head shoved into this teen’s butt, the tall man brushes it back and smiles even wider than before. He plops himself on the ground behind her, his dick standing stiffly from his lap. “You’re wild, baby, why don’t you get that ass to work already?”
Before Kat can respond, you make her breasts bounce in place, propelling her backwards just so that she sits directly on his cock. Kat yelps in shock. Her ass is so huge that he can’t make it past her cheeks, but you’ll soon fix that. As her panties you wriggle downwards, her giant bubble butt slowly squashing out of place until it’s totally exposed. You settle around her thighs, still maintaining enough cover over her crotch to maintain leverage, and you start her behind bouncing.
The man, grinning, places his arms behind his head to relax and enjoy the horny slut bouncing on his cock. Kat, however, is doing her best to discourage this. “OOH!” She grunts with each fall, as his generously sized cock manages to penetrate her each time. “AAH! You don’t... OOH! Understand, I’m OOF! Not doing this AHHH!”
To prevent her from putting up too much of a fight, You quicken your pace until she’s jackhammering his manhood into her bouncing butt. Her protests quickly lose coherence.
“NO-OH-OH-OH, STO-O-O-O-P! OH-OH-OH-OH GO-OH-OH-OH-OH-OD! LO-OO-OO-OO-OO-OOK AH-AH-AH-AH-AT MY-AY-AY-AY TITTIIIIIIEEEEEEEEEES!”
Sure enough, your rapid pistoning of her ass have caused her breasts to wriggle free of her bra, and they’re wildly bouncing in full view of the crowd. Looking around in panic, she sees several of the men in the crowd jerking off to her massive jugs. She tries to catch them between her forearms to stop their bouncing, but only succeeds in pressing them together as if showing them off. They wiggle in her grip as the gyration continues, and her oversized nipples rub against each other lewdly.
Kat’s makeup runs down her face, however her expression seems caught somewhere between surprise and pleasure. You’re working double duty as you continue to make her butt rise and fall, but you use the front of your panty self to rub and pinch at her pussy, sometimes wrinkling enough to work your way inside and reach her clit in the confusion. “I... don’t... want... this... I’m... not... doing... this!” She gasps. “Why... does... it feel... so...”
“Say it honey!” The tall man says. He’s reclined completely now, carefree and letting her do all the work.
“It... feels... so... GOOOOOOOOOOOD!” Kat screams. You feel an immediate surge of moisture, and you soak up her pussy juices with glee. You’ve succeeded in your revenge and more, you control your sister’s body so completely that you’re forcing her to take a stranger’s cock in the ass.
“It made me cum...” she whimpers, letting go of her breasts to hide her face. They flop freely once more. “Please, no more... no more.... oh god! I’M CUMMING AGAIN!!”
“Yeah honey, cum for me!!...” the tall man grunts, and he grips her ass tightly to stop it bouncing. For a split second you wonder why, until you can feel more liquid pooling around you, this time from both sides. Kat lets loose another torrent of her own at the same time her huge ass is being pumped full of cum.
You release Kat from her bouncing, and she immediately flops to the ground, panting heavily. You subtly stretch and contract over her, smearing his cum everywhere you can as the man stumbles to his feet, thoroughly dazzled.
“God damn, girl! You gotta gimme your number after that... or at least those wet panties...” he mumbles, his softening cock dripping on the ground. Your sister simply moans.