Jon held the rock, and thought intently about what they could do to restore Karyn, or at least make life easier for her.
Then, things got weird. Jon's eyes closed impulsively twice in a row, and when he opened them, Karyn was staring at him, mouth agape.
Jon now had C cup breasts, with the body to match! His hair, while still boyishly cut, was now blonde.
Jon started patting his new body down, amazed at how it felt. Fortunately, he still male where it truly counts.