You remember what Mickey did. Not only did he change you, first he got rid of the wishes on Karyn. All of them. Even the hair and breasts. Which means...
"I wish for all of Mickey's wishes on me to be undone."
You're Jon, you have your penis, and you're your right age. You don't know how it happened, but somehow the stone gained the ability to reverse its own wishes. And there's only one thing you want to do now before going to sleep. Revenge on Mickey.
You could just make Mickey a 7 year old girl like he made you, but there must be something more creative you can do.
