She explains in detail

Zatanna took a deep breath, as if preparing for a long speech, and then started talking.

"Recently the Justice League has been having issues transferring already defeated foes to prison. They would wake up halfway through the transport, and start wrecking havoc again. Normally we'd have the heroes who captured them go with them as an escort, but for people like Superman, he's so busy that he doesn't have the time for that. And since most of the villains Superman beats are incredibly powerful, when they break free it's a catastrophe." She said.

I nodded, signalling that I understood and that she should continue.

"So, I took it upon myself to create something that would make defeated foes more docile for transfer: these stickers. The stickers were created using my special brand of magic, and while I can't explain the intricacies of why they work, I can explain what they do." She continued. "The stickers make everything that is said to them seem fine, and completely normal. It doesn't rewire anyone's brain, just temporarily makes it accept things it normally wouldn't. As soon as the stickers are removed, the person is completely fine, and the affects disappear completely." She finishes, nearly out of breath from her long spiel.

'Interesting,' I think to myself. 'So it's not exactly brainwashing, or mind control, just persuasion. It also sounds like the affect disappear if the sticker comes off, so I'll need to be careful.'