Karyn looked at Jon with shock. "I can't believe it! You turned my head round the other way?" Karyn looked down and she could see her back, her ass and the backs of her legs and her heels. She walked over to Jon, walking backwards with a smoothness as if she had been like this all her life (Which to Karyn's mind she had)
"Did you put a time limit on?"
"Of course," said Jon, "Five minutes."
After a few minutes, Karyn's head span round and settled the right way. Karyn looked down. "Shit, this looks weird." she said. She tried to walk forward, but stumbled and fell.
Jon thought that wad odd, but then realised that the stone had changed Karyn's head round, so that she thought it was always that way round, but when it had turned it back, Karyn still thought that she had always been the wrong way round. Jon thought he could reverse that with a wish, but he was having too much fun.