Peter does follow after Bonnie when she gestures, and he is grateful she is not trying to run away from him this time. He stops as they reach the greenhouse, looking over at the book more openly now that Bonnie seems to be giving him permission to do so.

"...you're a witch," he says softly. He meets her gaze, because he understands that is a huge reveal. His gaze drifts over the pages of the book though he doesn't understand what is written there. He doesn't think he is meant to. It's clearly for witches if what she was secretly doing had to do with magic. "It's why you think you can get you and your best friend back. Magic brought us here. Magic would be what could bring us back. That's really smart. Also, definitely dangerous."

And he doesn't even know much about magic but he can figure that out. "What's this book?"