"That's right," he says softly. "You told me that." And he hasn't really had time to process it since.

He doesn't really want to process it now! His brain would much rather fix on esoteric lore from Koumyou's world than the fact that he might die if anything happened to the train.

"I have to admit, I don't really understand," he muses. "There's one for light, and for banishing the darkness? Doesn't the light do that by its very nature?"