[ He doesn't want to outright blame humans for what they did... even if it is the fault of some humans. But to just outright say "yes, they did something awful to us" would be against trying to be an Ambassador of the Monsters to humans. ]

Over a thousand years ago, a war broke out between humans and monsters. Both sides fought really hard! Over... something. I don't really know what. But even when the monsters tried their best... Monster souls just aren't as strong as human ones. The humans won, and sealed all monsters underground behind a magic barrier.

B-But it's gone now! We're all working on putting the past behind us! I really like the surface, and humans!!