Butcher Bird: A Novel of the Dominion (PB) (2017)

Spyder Lee is a happy man. He lives in San Francisco and owns a tattoo shop. He has his favorite drinking buddy, Lulu Garou, and other friends all over town. One night a pissed-off demon tries to bite his head off and he's saved by a stranger--a small, blind woman with a sword as wicked as her smile. After that, Spyder's life is turned upside down.

The demon infected Spyder with something awful--the truth. He can suddenly see the world as it really is: full of angels and demons and monsters and monster-hunters; a world full of black magic and mysteries. These are the Dominions, parallel worlds full of wonder, beauty and horror, of which Spyder's is only one. Each Dominion is home to another race of creatures from human myth. If you're clever or lucky, you can pass from one Dominion to another, but the Dominions themselves never touch.

At least, they're not supposed to. The Black Clerks, infinitely old and infinitely powerful beings whose job it is to keep the Dominions in balance, seem to have new interests and a whole new agenda. Dropped into the middle of a conflict between the Black Clerks and other forces he doesn't fully understand, Spyder searches for a magic book with the blind swordswoman who saved him. Their journey will take them from deserts to lush palaces, to underground caverns, to the heart of Hell itself.