Mike and Sei stared for a moment, and then Sei started to chuckle. "Oh, man! I hope you liked that bear a lot, 'cause it looks like you might need him. You look like you're four or five years old!"
A glance down confirmed the awful truth for Mark. He was little more than a toddler, his hard-won muscles gone. "No! I don' wanna be a little kid!" Tears started to form in his eyes and he stuck a thumb n his mouth without thinking. "I wanna be a big kid again!"
His two friends stopped laughing - Mark sounded like a little kid, too. Mike squatted down, concerned. "Mark? Think real hard. How old are you?"
The little boy frowned, then held up four fingers. "I'm a big boy! I'm four years old!" Then he picked up the teddy bear and hugged it. "Who are you? And where's my mommy?" He doesn't seem concerned about being naked, and also doesn't seem to remember that he should be a teenager.