"Darn it, Karyn!" Jon (or rather, Jennifer) shrieked. "This isn't funny! Even when the month is up, I'll be stuck as a girl since I can't reverse your wish!"
Karyn nodded sagely. "Well, then," she said, "we'll just have to retrofit my wish with a time limit. I wish that my wish for Jon to be female lasted for a month minimum, after which I can end it whenever I want. I also wish that only I can end it by any means, and that no wishes can affect my desire to end it. Furthermore,I wish that I controlled Jon's wish for the world to be this way under the same criteria."
Jennifer could only gape in horror as Karyn rattled off wishes. Ears back, she began to growl. Karyn smirked. "Oh, come now. I could have forced you to act like a girl, you know. Or better yet, made you think like one. As long as you get through the month with no change-back stunts or retaliatory wishes, and I feel you've learned your lesson, that'll be that and you'll go right back to being you again. On the other hand, if you try anything funny like revenge wishes or something, you cancount on beinga foxgirl for the foreseeable future. Here's your stone back, Jennifer dear."
Still snarling, Jennifer snatched the stone back from Karyn and stomped off to the school library to research her new form. She couldn't believe it, but she was looking at a whole month as a petite foxgirl.