"We're not really controlling them, either," William mused, watching as his mongoose sat alertly back onto its hind legs, studying the magical foe, and then promptly went batshit insane attacking what William suspected was its new favourite toy. "I mean, we don't control a Patronus either, beyond conjuring it, but they really only have one purpose."
His mongoose made a complete circuit of the room, faster than anything had a right to be, and leapt for the solar system again. William considered the size of Pete's laidback lion and shook his head. "It's a good thing you switched rooms," he commented. "Otherwise I think you'd be in trouble."