I'm.. not sure there are demons to hunt, here. Just Pokemon.

Which is actually what you have there. A Scyther, to be precise. They're pretty powerful, so I guess you got lucky about that.

[Okay, this is a bad explanation. She clears her throat and decides to start at the beginning.]

This new world is filled with creatures like that. We've been brought here to capture and train them to be powerful fighters. Or, for some of us, to breed them, but I kind of doubt that's going to be your goal here. They're called Pokemon.