Karyn knew that David liked Jon, but that Jon wouldn't have anything to do with someone female from the waist down. (Since Karyn didn't hear Sarah's wish on David, neither she nor Jon knew that his condition was new.)
"I wish that you would do to David everything that you wanted to do to me, and can be done without more wishes. I wish he'd agree." If Jon really just wanted to see her naked, fine. But if not....
