"Well, then," said Karyn, "there's just one more thing."
"What?" wondered Jon.
"You may be more in control than a wish, but it's not as good as a wish. If you make a wish, people think that things were always the way you changed them. If you just change shape, they don't. Why don't you add that ability?"
"That sounds good. I wish that my power to change myself will affect reality so that I was always that way, except that me and Karyn and anyone else I want will still know about the old reality."
Then Jon changed back to Jon, and back to Karyn again. "There," he (she) said. "Now as far as everyone knows I'm supposed to look like you. It won't look weird at all."
But then it dawned on both of them at the same time. The room was now empty of anything except a couple of boxes and an old, dead, potted plant. "There's nothing here!" said Karyn.
"Wait a minute," said Jon. He concentrated and became Jon again. And magically, the room turned back into Jon's room. He looked around and said "I see."
"I get it," said Karyn. "If reality changes so that you look like me, you're probably related to me, so you're not living here any more."
Jon said "Yeah" and concentrated again. He turned back into Karyn, and the room shimmered. But it was still a room, just a girl's room. A bit more pink, a stick of lipstick lying on a dresser. "That's strange," he said.
Jon tried several more transformations. Each time he became Jon again, he got his room back, but there were a couple of different ways the transformation to Karyn affected the room.
Finally, he said "You were close, Karyn."
"Okay, I don't get it."
"When I become you, there are different ways for reality to change. I could be related to you, and I'm not living here, so the room is empty. I could just look like you because of coincidence, so my room is still here as a girl's room. Or maybe I'm related but I'm visiting, so it's a guest room. When I change, it just picks one of those possibilities at random. Which means that I need one last wish before I can put away the stone."
Karyn waited.
"I wish that when I change myself and change reality to fit, if I want it to change in a particular way it will change in that way instead of randomly."
And Jon finally put the stone in his pocket.
Jon paused for another two seconds to concentrate. Karyn saw him transform until once again he looked identical to her.
"You look like me again," said Karyn.
"Yup," said Jon, in Karyn's voice.
"Did you have some particular reality change in mind that explains why you're just like me?" asked Karyn.
"Yup."
"So what is it?"
