Nautilus Than Perfect by K.L. Hiers

Detective Elwood Q. Chase has ninety-nine problems, and the unexpected revelation that his partner is a god is only one of them.

Chase has been in love with Benjamin Merrick for years and has resigned himself to a life of unrequited pining. But when they run afoul of a strange cult, Merrick’s secret identity as Gordoth the Untouched slips out… and so do Chase’s feelings. The timing can’t be helped, but now Merrick thinks Chase only cares about him because he’s a god.

Even more unfortunately, it turns out the cultists want to perform a ritual to end the world. Chase’s mission to convince Merrick his feelings predate any divine revelations takes a back seat to a case tangled with murder and lies, but Chase doesn’t give up. Once he finds out there’s a chance Merrick feels the same way, he digs in his heels. Suddenly he’s trying to court a god and save the world at the same time. What could possibly go wrong?