When Susan's daughter, Stephanie, arrived at her classroom, she was met by a substitute teacher. "Mrs. Lee won't be able to come today since she has gotten the 'Bear Virus'. I, Mr. Pennington, will be your teacher until Mrs. Lee is fit to teach again."
Stephanie was beautiful like her mother, except that she didn't inherit her mom's curvaceous body, though she compensated with a well-toned body from the amount of exercise she does. Her breasts were a firm pair of B-cups and her butt the smallest of all the girl's in her class, Stephanie herself was the smallest at 5'2" tall.
Getting infected by the "Bear Virus" made all of Stephanie's classmates, at least the female ones, worry. The fact that such a virus would turn them into big men, excessively fat or muscular, with a bunch of hair in their bodies, disgusted them. Stephanie thought that it wasn't a matter of whether they were going to get infected or not, but rather when were they going to transform. Take Mrs. Lee for example: yesterday, she was a woman walking through the school halls, and now she became a bear. What Stephanie hoped for was that she became a muscular bear at least, to not make all her sessions at the gym worthless.
A rumble was heard from outside, and an announcement came from the speaker. "Attention. Some people on campus have gotten the virus and began to transform. We advise everyone to get as far as possible from the infected to avoid getting hurt during their transformation. If any female student or teacher is feeling sick, report yourself to be let out of the building ASAP." Said a deep voice, instead of the sweet voice of the lady that did the morning announcements.
This announcement only served to scare the girls even more. The guys were just speculating on who was going to be the next girl to transform in their classroom, thinking about how their girlfriends will look after the transformation, and trying to find out the source of the rumble heard before.
A few minutes passed, and Mr. Pennington began the class, just to be interrupted again by one of the female students, who claimed that she was feeling sick, followed by another one, and then another one. Suddenly, Stephanie began to feel sick too, feeling a strong stomachache. "Please, anything but that" she said to herself. After a couple of seconds, the first girl to transform was a black-haired Asian girl, whose whole body began to swell and grow, gaining huge muscles that made her clothing explode, pecs, a full beard in her pale face, and a new 5 feet dick. The rest of the girls soon followed, all of them going through the same transformation, becoming humongous male bodybuilders with dicks the size of a door, breaking the ceiling and walls. The only one that transformed into something different was Stephanie.
Stephanie was growing too, but instead of muscle she was gaining fat and lard. "You got to be kidding me" she said as her voice got deeper. Stephanie's toned abs seemed to melt, and her perky breasts grew to become man boobs. She didn't want her cute black shirt and brassier to be destroyed, so she took them off, but her expanding legs and growing feet devastated the baggy jeans and boots she was wearing. Greases and pimples adorned her once petite face, alongside a quadruple chin. The brown hair in his head got shorter, but more appeared on her arms, legs, back, and belly.
Stephanie knew that there was only one change left. "Just get it over with" said the almost-bear, hearing his new voice, struggling to get his hands to cover his mouth, due to their sheer weight. He couldn't see it, but her clitoris was growing, forming a new penis in his crotch full of hair. "Maybe THIS will be bigger than mom's" thought Stephanie, but his dick stopped growing at 4 feet, 2 feet shorter than his mom's. A sack came from her crotch, along with her new basketball sized testicles. His dick was the only thing not covered by hair.
The transformation was done, and it was then that Stephanie noticed he became the tallest in all the class, growing to 12 feet. This time, he was bigger than her own mom. But he didn't have much time to think about that, since he began to feel a sudden urge. He stroked his new dick, and in a second shot a stream of cum. The classroom had been long evacuated by now, only the girls-turned-to-bears were left, and the remains of the classroom were stained by cum.