"I don't think demons are meant to be a good time," she points out with a tiny little smirk.

"Someone who comes here sometimes, Katsuya Suou, he comes from a world full of demons that... are trying to eat everybody and end the world I think. They found a way to open his portal and followed him here. People killed most of them, most of the leader ones anyway, and then someone fixed the portal so demons can't get through. If you want more details you'd have to ask Katsuya."