Karyn realized that although wishes could not be reversed, there was a loophole. It would be possible for something else to reverse a wish... if you wished to be dressed, for instance, you could still take your clothes off and reverse the wish by yourself.
"I wish that in five minutes, me and Jon would be about to have an operation to separate us. I wish that the operation will succeed, and that once we're separated, we'll transform so that we aren't crippled, and nobody except us will remember what happened. Now you can speak, Jon, but don't get too excited while I'm part of you."
"What did you just wish for?"
"The wish can't make me not be your penis. But a doctor can. Once the doctor separates us, then a wish can transform us so that we're okay--otherwise we'd have one leg each. And once we're separated, you can get as excited as you want... but if you play with yourself, make sure it's yourself."
And minutes later....