How about a bet?

"How about this?" Charlotte said, rubbing her chin in thought. "If anyone thinks you're a full grown, adult woman and not a little boy, you get my clothes, and I have to wear or do whatever you want!"

"YES!" Lauren desperately agreed at the opportunity to finally turn the tables on her rival.

"But, you can't just tell anyone." Charlotte explained. "You have to play along, and see if they figure it out on their own!"

"Fine, no problem." Lauren said.

And, she truly thought it was. Sure, she had an embarrassing outfit and haircut, but she was a grown ass, 20 year old woman! Not just any woman, but a sophisticated debutante! It should be no problem to win this bet!