By the time the girls arrived to the lockers room, Erika could tell something was amiss. As she pulled down her skirt in front of her locker to change her clothes, two things became immediately obvious.
The first thing was a tiny bump on the front of her panties. The second thing was a wet spot between her legs. She squeezed her thighs together to conceal it, and met some resistance as a sack with two small balls pushed out of her lips, jutting her clitoris one inch forward. Another wet spot began forming in the middle of the small tent it made.
"Let me know if the uniform is too big for you" Erika heard coming from behind. She hurriedly pulled up Melissa's gym shorts before anybody could notice her problem. They were only a little too big - and probably too small for Melissa since her recent growth spurt - but that was just perfect to conceal her mutant clit.
She put on Melissa's shirt as well - also loose and revealing a bit of cleavage, but she had no other option.
Meanwhile, Emily's PE uniform hugged her new curves tightly, making her visibly uncomfortable. Erika felt her groin tingling intensify and she dashed out of the locker room for the coach's roll call. She watched as Melissa approched the coach to excuse herself from class. She looked genuinely nauseated on top of not having her uniform on, and the coach was easily convinced to let her sit on the bench for the hour.
The class started running around the gym to warm up, before moving on to do jumping jacks and other exercises.
Erika tried to focus on her breathing. On the plus side, her tight panties kept her one incher from flopping around her shorts wildly. On the other hand, the rubbing of the fabric didn't exactly help with her frustrating sex drive, and the femininzing effect of the goo she had ingested was fading more rapidly by the minute.
As the class warmed up and the coach gave instructions for the volleyball drills of the day, Erika's clitoris had grown into a baby dick and was slowly cramping up her panties. She tried to keep her head down and not look at her classmates, which would elicit a delicious tingling in her thickening stub even though they weren't as developped as Melissa or even Emily at this point.
Oh and Emily... Erika could pick up her scent wherever she was in the room. It had become a mix of flowery laundry power, faint sweat, and canine heat. Each time Emily brushed past Erika, the latter would feel an almost physical pull to pin her friend to the floor and kiss and mate. It was becoming unbearable.
A spasm ran through her tiny dick and it oozed some pre, which quickly smeared in her panties as she was doing a volley drill. She felt it slip upward and push against the little bow near the waistband of her underwear.