Kaiba clenches his fist. That Noa had been a blip of data so easily erased...it was unsettling to think about. He's certain he could have done something, if only he'd had the chance at the right time.

But now he didn't need to. Now they have this.

He shakes his head. "I'm willing to let the past lie. You acted to win Gozaburo's favor, and I know exactly where that leads. You stopped him in the end. But...before you go, take this."

He reaches into his bag and pulls out a small notebook.

"You'll find that the wall of your dormitory's common room has a board where you can post notes. The notes posted there will copy to every common room in the school, and the individual housing areas. This book has a similar enchantment, but with one difference: when written in, the only place it copies to is the book it's paired with. I have the other."