[Suzerain of Sheol]

That's a complicated question, it really depends how you define religion. There really isn't any point in organized worship at all, anymore, but at the same time the supernatural mystic cosmology of the Judeo-Christian tradition is manifestly, observably real, so faith is totally out of the question, too.

So, while we have "priests" they serve an almost entirely different function than they have in any historical and extant society on earth. There's no longer a social component to "religion", it's a science, and a highly militarized one at that.

I can't speak for everyone, but neither of my characters worship or venerate anything, though they obviously accept the existence of demons, angels, evil spirits, heaven, hell, etc. As well the truth that the God who created the world, and they both formerly prayed to, has been destroyed.