Shady Depths - B. L. Brown - Bog

A witch running from heartbreak, a merman who hunts the stars, and the Shade which binds them both.
Keir Simmons, a bounty hunter for the Coven for the Regulation and Oversight of Witches, has made a career out of running away from his problems. Blindsided by a break-up, he leaps at the first assignment he's offered, one that will take him far away from his ex: chasing a rogue lorelei to the edge of the European continent.
When a chance encounter with a midnight diver leaves the pair inextricably linked, Keir is caught between his responsibilities as a C.R.O.W. Enforcer, his past as a questionably wicked witch, and his broken, but beating heart. With C.R.O.W. breathing down his neck and the lorelei continuing to evade capture, it becomes harder and harder to turn away from his unlikely ally - a man with a secret lurking just beneath the surface.