The first half of the day was torture to Erika. While Emily sat next to her in class, peaceful and content after breeding with Piper, Erika had turned her body female temporarily, but the ingested goo's aphrodisiac effect was slowly hitting her. There was a damp spot between her legs, seeping through her torn underwear, and as she stood up after her class she noticed a little wet spot on her chair; she wiped it discretly.
She forced herself to stay around other people through lunchtime, certain that if she were alone with Emily, she would absolutely mount her and make her breed senseless. Fortunately, or unfortunately, the goo's effect didn't last very long on Erika anymore, and as she was sitting through her afternoon classes, she recognized the familiar warmth on her groin as her clitoris was shifting and lenghtening into a penis again.
The changes were slow at first, but during the last hour of school, Erika's transformation back seemed to speed up. She was scribbling notes down when she watched as her breasts progressively deflated until the front of her shirt was empty. On the contrary, a bulge was forming between her legs: her clit had swollen into a male member paired with a full ballsack that were forcing her legs apart.
As the bell rang and Erika stood up to exit the classroom, she saw the front of her skirt was jutting out, and she pressed her bag in front of it, hushering Emily out.
"Hurry up Emily, we don't have more time," Erika whispered in a masculine voice. She walked brieskly arm in arm with her friend, all too aware of her shoulders broadening again and her body becoming more toned. Once outside, they practically ran to Erika's house, both of them trying to ignore the male packages bouncing around under their school skirts.
Closing the house's door behind them, Erika ordered Emily around.
"First, text Piper and Riley to remind them to come here. Then, take snacks from the kitchen's cupboard so we have something to eat, I'm famished... I'm going to check on Max in the garden real quick, I'll be right back."
Erika went to the backyard, partly to check her husky dog Max, partly to check on her puppies that she had put in the garden in the morning. To her horror, none could be found. Looking around the garden, she found a hole behind a hedge in the back fence, where the growing puppies had surely vanished.
She didn't have the time to think about the ramifications of mutant teenager dogs running around town though, and came back to Emily, who was setting up the snacks on the TV table along with glasses and orange juice. She quickly ran to her bedroom to have a change of clothes, removing her ill-fitting and damaged school uniform, in favour of a loose t-shirt and jogger pants she usually kept for sports. She returned to the living room.
Checking her text messages, Erika made sure Cole was coming too, and shortly thereafter, Piper and Riley knocked on the front door. Cole was the last to arrive, and Erika frowned as she noticed he had brought a friend of his - a girl. Erika's enhanced nose caught her scent and could tell immediately that Cole had impregnated her, and she smelled like she had been exposed to the vial that had fallen into the swimming pool.
Everybody sat on the couch and floor around the small TV table, looking at each other awkwardly, until Erika began:
"You're all here because something has happened. Something impossible and strange, but you're all affected by it..." she said in a deep voice.
"Wow, what's up with you Erika, did you catch a cold?" Piper joked half-heartedly.
"This is what you need to know about actually. We were all exposed to an unknown chemical, and it has changed us. It has changed your bodies. You know what I'm talking about..." Erika pressured, and Piper and Riley both looked down.
Cole cleared his throat. "I think it probably happened when you went over to my house for Melissa's sleepover. I think the swimming pool was contaminated, and you were all exposed. So was Sam," he gestured towards the girl he had come with.
Riley turned a little pale. "But, that doesn't make any sense. Things like that don't just happen... It's impossible."
Erika snapped in a commanding voice. "It's the truth and you know it. Remove your shirt and show everybody. Piper, you too."
Both Riley and Piper turned red and froze for a second, but Erika's order was impossible to resist. For a reason they couldn't fathom, they felt compelled and in fact happy to comply. Unbuttoning their school shirts, they exposed themselves to the room. Everybody's eyes looked down, transfixed on the swollen breasts and teats lining up the two girls' bellies.
Riley's already dark aureolas had turned a darker shade of brown over her olive skin, and her feminine breasts had grown larger than before the sleepover. Piper's thin body had also filled up, her chest fully developped. They looked very different though, Riley's wavy dark brown hair contrasting with Piper's short blond pixie cut. Their face retained a bit of innocence, even as their bodies looked older in development.
"I'm sure you felt it, too," Erika went on. "The heat. Your body changed, and you haven't been able to help yourselves. You've been overwlemed by new impulses, urges. That's the same for everybody in this room, though some of us changed in different ways."
Erika paused for a second. She wasn't sure about mentioning all the details of the original salve.
"Cole, Emily, take off your clothes now."
Emily immediately executed herself, removing her shirt, skirt, even panties in front of everyone, trembling a little in the cool air of the house. Her 3-inchers sprung forth and began to harden from the sight of her classmates. She had almost no breasts. Some red colored her cheeks under her freckles.
Cole flinched and tried to resist for a second, before finding himself unable to. Slowly, he removed his clothes one piece at a time, until both Emily and him were sitting naked on the floor, and everybody could see their enlarged genitals. Cole's in particular were shifting as he was getting harder, ressembling more and more a canine shaft with a red rocket protruding, already 6 inches long. There were also faint canine nipples on both him and Emily.
"You too," Erika issued to Sam, who executed herself.
As Sam lifted her hoodie and shirt over her red hair, her round belly became apparent to everyone. She looked maybe 4 months pregnant. Her breasts swayed along her movements, and the rows of teats underneath poked outward following the curve of her belly.
Erika pointed to Sam. "This is what will happen if you follow your urges blindly. Not only that, but if you get caught, don't you think doctors will take an interest in you? What if we get locked up in some laboratory?" Several faces in the room turned a little pale at the thought. "This is why you can't tell anyone else. It has to remain a secret between us."
At last, Erika herself got naked in her full male glory, her young lithe yet masculine body more toned than before, flat chest, and canine nipples on her six-pack. Between her legs, an over 6 inches cock impossible to ignore, which was soft yet also twitching faintly. More than that though, the light brown hair on her groin looked like fur and had crept up her belly button.
"This is what happened to me. I was exposed more than once to some substance, and each time it made me look a little more like a dog. Not only that, but each time I cummed in someone's belly, I also became a little more like a boy. So did Emily."
"And I didn't used to be female," Sam added. "I mean, I knew I was always a girl, but before bathing in Cole's swimming pool, my body was male. And then I also ingested cum and it made me fully a girl, and I fell pregnant."
"By magic? And whose cum?" Riley snickered.
"Cole's," Sam replied without blushing. "I'm his girlfriend."
Cole turned red as a beet while everyone save for Erika and Sam made faces thinking about what had happened between the two of them.
"This isn't a normal pregnancy either", Erika went on. "The development is over in a matter of days, and it is critical that you hide it from everybody at school and in your homes. You can't let your parents know about it."
"What about the babies," Piper asked.
"There are no babies. You're not pregnant with humans. You will birth puppies, and if you don't get sexual stimulation regularly, your body will also turn into dog bodies. I'm sure you've tried that at first, resisting the urges until you felt it, in the dark of the night; the fur creeping on your skin, the canine teeth in your mouth...
Nobody said anything in protest, and everybody carefully avoided looking at each other.
"I'm taking command in the group now, because I'm the most experienced, as I was the first to change. This is why you need to listen carefully." Erika concluded.
"Wait a second" Cole protested, "I'm the oldest, I should be in charge!"
Piper giggled. "You're an irresponsible idiot," Riley snickered, "there's no way any of us are listening to you. Teenage boys are too immature!"
Erika pierced him with inscrutable eyes. "I'm the alpha. You're not even a beta, you're like, omega on my list. You better do as I say", she growled in a low voice.
Everybody became very quiet very quick, silenced by Erika's natural authority. Erika savoured her power move for a second, then continued:
"You think we should listen to you because you have a big dick? Jerk, you're just weak. If you're not here to help me, you're merely an annoyance, not a threat. But I think we can start with our first lesson here..."