"This is bullshit." Michael whispered to himself as he sat at the back of class, his legs crossed under his skirt as he kept pushing the annoyingly long, dark hair out of his face. He was hating being trapped in the body of his twin sister Lena, but his mischievous sibling had discovered a magic transformation app and was using it to inflict a cruel prank on her brother by swapping their bodies. So not only was he a girl now, but during the school day Lena had been using the app to give her old body even more changes to bring the embarrassed teen into the center of attention - thicker tree-trunk thighs, a flat stomach, wide child-bearing hips and breasts so absurdly big they would have felt at home on some lewd hentai model.

Sighing as he sat in the back of class, feeling his massive boobs resting on the desk as they obstructed the lower half of his view, he felt a now-familiar warmth in his body. Lena, from the front row, was already secretly adding more changes. He felt a cushioning in his swelling ass as it expanded to cover the entire seat and more, excess weight sticking out over the sides as his panties rode up his crack like a naughty thong. Groaning as he adjusted his skirt he felt his breasts expand once again too, the fabric in his uniform barely enduring as they swelled up several extra cup sizes until they looked even more comically large. They were now the size and shape of ripe watermelons and they dominated his upper body, weighing dozens of pounds each. The worst was still yet to come though, as when the teacher called for 'Lena' to come up and help with an equation Michael squealed, feeling the painfully divine sensations of a massive, thick, elephantine 5-foot phantom cock being rammed inside of his tight pussy for a few seconds!

He could hear the real Lena giggle as she echoed calling out for Michael's new name ("Lena!"), the boy-turned-girl pressing his hands firmly into the desk to stop himself from screaming in insane pleasure, nails digging into the wood as his eyes rolled back into his head. He almost drew blood from biting his lip as his body begged, no, demanded to be pleasured. However, he needed to stand up and solve the problem to stop his teacher from continuing to call his name, so he got to his shaky legs and tried his best to focus on just getting the work done already.

"Fuck me..." Michael whispered in complaint as he strode towards the blackboard, feeling acutely aware of all the feminine sensations his new body was shouting at him. He could feel his thick thighs rubbing together under his skirt and his gigantic, half-exposed butt shake as his enormously heavy breasts bounced uncomfortably with every step, the gaze of his classmates in the aisles burning into the back of his neck they stared at the incredibly curvy student trying his best to avoid their attention. With a quivering hand he picked up the chalk and began solving the equation, his titanic booty cheeks sticking out the bottom of his skirt as he bent over to survey the question. Working out the numbers in his head, his boobs pressed into the board as he tried his best to ensure that the buttons on his uniform didn't give up under the strain and expose his jugs to the rest of the class. It was hard to keep still in this new body, especially while still recovering from the sensations of being fucked temporarily by a well-hung stud, and the giggling from his sister in the front row made it all the more awkward.

"What's wrong Lena? You're taking your time, Lena." the teacher asked, parroting her victim's name, and Michael could barely focus on anything at all at the repeated triggering of the ghost dick once again. Lubrication began to drip down his thick inner thighs as an ecstasy stronger than anything he'd ever felt before gripped his body. He felt himself feeling so unbelievably full and satisfied by getting rammed by a giant penis, barely giving his own body enough warning before he threw his head back and screamed in the pure, impossibly intoxicating sexual pleasure of the enhanced female orgasm.

Falling to his knees, gasping and barely able to think straight, he could hear the teacher's voice somewhere far off in the distance demanding he go to the principal's office for his 'prank', but it would be a few minutes before he would be able to walk again. He just hoped it wouldn't get any worse...