Kaiba doesn't respond for a short while, but he drops back to lean against the wall. His fist stops shaking, and his breaths even out a little.

"Life was so much easier when I was alone," he grumbles, reaching up to rub at his temple.

After a while, he finally looks back at Jonouchi. "Fine, I won't rush anything. But I need to process this. I wonder...if there are that many alternate timelines converging, if no one on the train is from the same one as someone else."