"I wish that Jon would come back here, open the door, walk in, and say 'the crow flies by tonight'."
But Allison hadn't had the stone for long. In fact, since Jon's grandfather had sent him the stone, nobody had had the stone for long. So she really had no idea how to keep it safe.
Taunting someone physically equal to yourself in a face-to-face confrontation, with no allies to support you, inside their own house, was a really lousy way to keep the stone.
As Allison made her wish, Karyn plunged her fist into Allison's stomach. Unprepared for the idea that even a usually nonphysical person might fight if cornered, Allison took the blow full force and went sprawling. As the effect of the blow hit her, Karyn stomped the heel of her shoe right into Allison's breasts, not giving Allison a chance to get up. Allison seemed about to make a wish, but was unable to while having the breath knocked out of her. Allison tried to fend off Karyn's further blows by kicking, but missed once, which was all it took to give Karyn a chance to place a hard kick into Allison's skull.
Allison fell unconscious and blood was seeping out of a gash on her face.
Karyn felt sick. That was far beyond what her self-defense lessons had taught her, which was to hurt the attacker enough to escape--but escaping from someone who had the stone wouldn't be much good. Still, she knew it wasn't over. She reached for the stone but somehow found herself unable to grasp it. Touching the stone that Allison was still holding, she said "I wish I knew what was wrong."
Oh. Allison had wished nobody could take the stone from her.
"I wish Allison's unconscious body would give me the stone."
Alison let go of the stone and it fell right into Karyn's hand.
"I wish Allison was at home, that there was no evidence connecting me to her condition, and that if she tried to tell anyone I hurt her they wouldn't believe her." The body vanished, and so did the drop of blood that had fallen on the floor.
Of course, few jobs are fully done. At this time, Karyn heard the door open downstairs. Wasn't it locked? But she heard it open anyway, and then someone was coming up the stairs. The door to her room opened and she saw that it was Jon. Not quite clear why he was doing it, he said "The crow flies by tonight," and then fully came to his senses to see....
