Trick Of Light by Mary Calmes

Jackson Tybalt is living his best life even though, to others, it might sound a little odd. For starters, Jackson’s a warder. Duty bound to patrol the city of San Francisco, doing battle with demons and things that go bump in the night. Second, Jackson’s married to an ex-demonic bounty hunter.
Raphael Caliva isn’t quite a man, more of a creature, with a very normal job as a general contractor, which he really loves. But what Raphael loves most, though, is Jackson. So much so that he’s sealed his fate to Jackson’s. If one dies, so does the other. No muss, no fuss.
This is the first of the surprises Jackson receives when he and his fellow warders meet one cold afternoon in February. Turns out, a blood witch they believed they’d vanquished has returned, intent on revenge. Nothing is as it seems, and now Jackson and the others have to prepare to fight not only an elusive enemy, but also the fatal curse she imparted.

But sometimes, it’s not quite as bad as it seems. More a trick of light than life and death. Or is it?