Angels aren't part of the 'Plan' in my world. They have to work through intermediaries, or else they'll break things, and they only showed up in the first place because reality broke and wasn't fixed properly. They're a pain in the ass to track, but that's because we don't usually have them around -- if you know what you're looking for, you can figure it out.

Werewolves can spot demons pretty easily as it turns out, because we really want them dead.