Dan grabbed the chair from Kat's desk and sat down. After a moment's thought, he sighed. "I'm at the age where I've just gotten the hang of being a guy, so I don't want to turn into a girl. Not even for all Kat's powers. So I don't want you to transform Kat's body, Mom. I want you to transform her mind."
"What?" Kat yowled. "No way will you turn me into a slobbering idiot or a mindless zombie, you little sidewalk licker!"
"Shut up," Mom said, not even looking at Kat. "What did you mean by that, Dan?"
"If she sees me as a powerless enemy she can torture without consequences, we'll have to go through this again. Maybe it'll be worse next time. Maybe you won't rescue me before she does me in. She's evil, Mom, what she did was evil."
"I can't argue with that," Mom said.
"So instead of changing her body into something, I want you to make her completely obedient to me."
"You vicious little toad!" Kat shouted. "If you try to make me obey you, I'll—"
Mom pointed her wand at Kat, who fell silent. "Go on," Mom said.
"If I ask her for something, she has to obey. If she wants to do something, she has to take my desires and interests into account. And she can't do anything to hurt me, so she can't get any revenge. If she obeys me, she can't hurt me. So just reach into her mind and make her completely obedient to me."
"No sooner said than done," Mom said, flipping her wand. A spray of sparks flew from the tip, sprinkling all over Kat's eyes. She tried to flinch back and block the sparks, but couldn't. The spell lasted maybe thirty seconds.
Finally Mom lowered her wand and stepped back. Kat shook herself all over, like she'd just come in from the cold, and looked over at Dan with a look that mingled adoration and contempt.
"She's yours," Mom said. "Anything you ask, whether it's to share her stuff or to use her powers for your profit, she'll do it. You and your well-being will remain her most important priority. If you want to make her your servant, use her powers to make yourself rich, or just get her completely out of your hair, she'll do it for you.
"But," Mom said darkly, striding over to Dan and poking her wand into his chest, "this isn't complete license to do whatever you want. This is her punishment, but if I find you've abused your authority, or put her in harm's way, or did anything out of proportion to her punishment, I will come down on you with the exact same wrath. Understood?"
"Understood," Dan replied, with a nod.
"Good. This is a punishment for her, and a test for you. Make me proud, both of you." With that, Mom turned on her heel and strode out of Kat's bedroom.
Dan and Kat stared at each other in silence. The moments piled up. They could hear cars racing by outside, and the neighbor's dog barked. Finally Kat relented, flopping down to sit on her bed.
"Fine, you rodent," Kat said. "What do you want of me?"