[Stupid nonsense, says the guy who just had his magical book saved for him by an actual demon.]

Demons and angels? Goodness, you must come from quite the place, then! [He only knows one Angel and that's more than enough tbh.]

But for it to not be common knowledge-- could it be that most people are simply kept unaware of all of it? That sounds rather similar to my own world, actually. Though I imagine it's much easier keeping things such as demons a secret when most of the population can't even see them.