She knows.

The tattoo simply said BELIEVES TREVOR. Casey glanced up at him, her mouth forming a perfect O, and blinked twice.

"I'm... stupid?" she asked. "I'm stupid. This thing really works! Holy shit, I can't believe it works! Think of what we could do with this!"

"You first," Trevor said with a smirk. She furrowed her brow and concentrated.

"We could... uh, rob a bank? Or, like, make other people like us? Wait a minute, I'm still stupid!" She scratched at the edge of the lettering on her arm and it peeled off easily. Casey stared at the small disc with amazement.

"It really made me stupid. I was actually slower while it was on me! Trevor, this is fucking crazy! What else have you got? How does it work?"

He showed her what he had discovered so far. She watched attentively, then grabbed it from him.

"Obeys Casey," she said, and before Trevor could object she took the disc and slapped it onto his forearm. Trevor scratched at the words desperately, but they'd already sunk in.

"What the fuck?" he asked angrily. "Why'd you do that?"

"Don't worry about it," she said. He relaxed immediately. "You put one on me that makes me believe everything you say. I wanted to correct the power imbalance."

"Makes sense," he said. "I don't feel different, but I guess-"

"Hop up and down," she interrupted, and he scowled and started hopping.

"Not funny," Trevor said, and Casey's grin disappeared immediately. She told him to stop jumping and he did so. They stared at each other awkwardly for a moment and Casey cleared her throat.

"I suppose we should both remove each others' tattoos," she said. It wasn't a command, so Trevor didn't act. Both were clearly making a conscious calculation - whether to relinquish power or try to seize it before the other could.