Jon concentrated, then asked the girl what her name was.
"My name is Jenna."
"That's better," Jon said. "Now, about your hair." He concentrated again. Jenna's hair changed from dark brown to blonde and became longer. "That's much better. But something's not quite right." He looked her over. "I got it." He concentrated and Jenna's size-C breasts ballooned into size-DD breasts.
She looked down at herself. "I don't really like this."
Jon was getting tired of her complaining. So after he concentrated again, she became totally obedient to him and was happy to be a girl. He decided to keep her like that, at least for the rest of the day.