frost_light and
melissa_writing posed this question that I haven't been able to post on until now because it requires me to think, and there's been precious little of that with our game 2 weeks from release. /panicmode
Night Life deliberately does not have a Judeo-Christian Heaven and Hell. I wanted it to be more ambiguous, and deliberately chose to spell "demon" "daemon" because the word "daemon" can mean either "god" or "demon"...it's essentially a god-like being from another world, which is exactly what the daemons in the Nocturne universe are. Some are good, some are evil, some are neither.
Is there religion? Absolutely. Some werewolf packs in upcoming novels are devoutly Christian. Some worship old Greco-Roman gods. Witches have their own set of beliefs, but they are actually less religious than weres, because when you draw your power from something, it's hard to also worship it as a separate entity. I also deliberately stayed away from religious symbols except for the pentacle, because I like it and it's used as a symbol of protection, so I had Luna wearing a silver one next to her skin as both physiological and psychological protection from turning were. Silver has a biological reason rather than a supernatural one for affecting werewolves--the vibrations of silver are at odds with the were blood, tinged with some hint of the Other. Well, I guess that's sort of supernatural...but it's not a symbol with the power of Faith behind it.
Basically, I guess I went with what I was comfortable with in Night Life. The pentacle will protect you from nasty magic, its energies interacting with black magic as a buffer, but you can't flash it at a daemon and howl "Begone, Satan!" You'll just get your soul ripped backwards out of your body.
BLACK ARTS has a made-up religion for the main mage character combining Egyptian myths, the Crowley Chaos magicks, and some other random bits I thought would taste good. The rules are more set--evil will always react badly to certain items, like non-saline running water (my main character can't even take a shower...she has to have baths or she'll crumple in a ball of agony under the stream.) Evil in BLACK ARTS believes that these things will hurt it, and I explore the belief vs. reality theme quite a bit, so I was able to take more on faith.
I think it comes down to what kind of book you're writing--Night Life has a cop for a main character, someone who's very factual and reality-based, while BLACK ARTS has a mage who has been raised in a mage world fraught with the unseen her whole life. Religion fits naturally there, even if it is made up. I, personally, think the use of symbols and religion is a personal choice and that as long as your rules are clearly set you can get away with a lot in fiction. That's what makes it fun, after all.