Half-Blood Origins by Natasha Brown

Love has no future for those who are worlds apart
For the first time in her rookie career as an enforcer, Emery must rely solely on her own judgment after her partner is forced on leave. Alone in an unfamiliar city, she is eager to discover the identity of the mysterious man who saved her life and the reason he and his friends have been following her.
Months of searching for Bane has led Tovin and his companions straight to the vampires—and the shifters. After learning of the escaped criminal’s malicious plans, they decide to reveal what the shifters really wish to know—who they are and why they need their help.
When Tovin and Emery are paired up in the search for Bane and his dangerous descendants, Emery suspects her handsome new ally is hiding something. In truth, Tovin has ulterior motives for being there. His interest in Emery could lead them both into dangerous territory—a realm where love is forbidden between those who live worlds apart.