Locke and Key: The Assassin SHifters book 24

Werewolf Locke Renfro has spent most of his life hunting and killing rogue werewolves - vicious murderers who take pleasure in causing misery and destroying lives. Including his own when they slaughtered his parents. After a rogue bites his lover, it triggers the process of turning him into a rogue also and Locke must kill the only man he ever thought he'd love. Years later, the fates have finally given him a mate - smart, funny and sexy Mitch Devan. Locke is afraid to seal their bond, though, terrified that it will make Mitch a target of rogues who despise him - who would love nothing better than to murder his soulmate. Mitch Devan has spent so long waiting for Locke Renfro to claim him as his own that he's not sure everything will work properly if the time finally arrives. But Locke has slain more than his share of rogues; he is convinced that mating with Mitch will put the human at the top of the rogues' revenge hit list. Mitch isn't sure that would be any worse than his platonic existence with the man he adores. When a simple business trip lands him in grave danger, Mitch finds out exactly how far Locke will go to retrieve the key to his heart. Loyalties are tested and enemies are revealed, as the Skull Blaster team comes together to rescue their own.