Mark put on one of his shirts back on. The vial had changed his body so much that the shirt hung down to the top of his thighs. And... he looked cute, he realised. The baggy, oversized sweater folded over his hands, the way he stood in front of the mirror with his legs just slightly crossed in a show of modesty, the way his blonde hair hung down his back. It was nice to look like this. It felt right. Like this was what he was meant to be.
Maybe he didn't have to change back. Maybe he didn't have to be a 'he'. 'She/her' certainly sounded better in her mind. She nodded, knowing she was always meant to be a girl. And if she really was committing to this, a change of name would suit.
After a few seconds, and a name came to mind; Milly. Yes, that would do nicely. Milly put her hands on her hips, loving the way the oversized shirt crinkled and hugged her curves as she did so, and smiled. She was Milly, and she was meant to be a girl.
A banging downstairs broke her out of her life-changing realisation. "Right, yes, I'm coming!" Making sure she was covered up enough, she scampered down to greet Jake.
Jake stared at the bombshell that had opened the door. "Who are you?" he said, rather dumbly.
"I'm Mark. Well, I was. But I realised I'm not really, anymore," Milly explained, like it made any sense. "Look, just come inside and I'll explain."
Jake staggered in, and barely made it to the couch without bumping into walls for all the oggling he was doing of Milly. She sat down across from him. "So. First of all, yes, I am Mark. I know you're Jake, my best friend and I know that in Grade 10 you told your mum you were at my house studying but really you snuck into the back of a nightclub, where you tried alcohol and immediately threw up over the bouncer as he threw you out."
Jake blinked. "Holy shit, dude. What... how the hell did you become this?" He waved a hand at all of Milly.
"I was getting to that!" Milly replied. "Look, this morning I found a mysterious box of vials at my doorstep and decided to try one. It turned me into this, but, shocker! I actually feel more comfortable as a girl, so I'd like to go by she/her pronouns now, if you don't mind. My name's Milly."
Jake stared, jaw on the ground. "I- what- how...?"