Violence / Gore: The violence ranges from a monster eating someone off-screen and the bare bones seen afterwards to someone basically exploding from the inside with a lot of blood shown. People shoot other people with guns and there's some boxing and other fights. Some characters have powers of regeneration so most injuries are less serious than they could be.

Nudity / Sexual Content: There's all kinds of fanservice and innuendo and at least 2 counts of strategically covered nudity. Fuyumi ends up in (fanservice-y) outfits a few times and she is visibly uncomfortable wearing them.

Theological Themes: It's set in what's called the demon world, but there aren't any actual demons per se, the characters are what I'd rather call monsters: vampire, werewolf, ghost, zombie, Frankenstein's monster. A lot of them can use different kinds magic but it's not elaborated on how any of it works. Fuyumi is shown tied to a cross in the OP, but the situation doesn't feature at all apart from that one image.