"Shit!" Drew immediately knew that he made a mistake. His bones started to shudder and he could feel his body start to shift in a few major ways. Drew knew his plan could go sideways but he didn't expected the fist part of his transformation. His eyes twitched and the world around him blurred. The original owner of this body needed glasses and there's no way Drew could find their exact prescription in the lost and found.
The specifics of his transformation were a little elusive to him, but Drew could tell that he had lost about an inch or two of height. The fat in his stomach seemingly pulled itself upwards into his pecks, causing him to develop a clearly female bust. His hips audibly popped as his pelvis flared out. Along his back, his hair slowly crept downwards until it laid against the square of his back. After a few moments, the changes settled down and Drew started to blindly feel around his new form. Drew could tell that his new form was a female roughly his age.
"You good?" Kate asked from outside the stall, her voice now distinctly masculine.
"Uh, yeah," Drew squeaked. "I used a random skate and forgot to bring clothes in with me."
"Oooo, female. I'll show you mine if you show me yours." Kate laughed, seemingly proud of her new body.
Drew was a little nervous but he decided to join her. He covered his new breasts as best he could and pushed open the stall door.
"That... well, that's a small problem."
"What? I don't feel deformed or anything. Maybe a little blind. I think my body needs glasses." Drew watched as Kate's blurry form walked to the other side of the room. After a minute, she returned and entered the stall with him. "No, no, no, no. No funny stuff! This is not cool!"
Drew forced his eye shut as Kate started to reach up towards his face. A second later, Drew felt cold metal against his ears. After a minute of nothing happening, Drew looked up to see an attractive twenty year old guy looking at him disapprovingly. It was then that Drew recognized the sound of his new voice. The last person to use that skate wasn't a random skater, it was Kate.