Defiance by Etta Pierce

Her scent was in his lungs, and they’d never even met.
Novak Gaul is a free agent on a short leash. Most of the time, he forgets that his life isn’t his own, but when a human woman’s scent latches onto him like she was meant to be his, he has to run the other way or risk the consequences.
Until his boss calls in a favor.
A highly illegal favor with massive personal and political implications. His human’s name is Charlie, and he needs to use her as bait. But when it’s time to let her get taken, will he be able to let her go?
For the sake of humanity, he hopes so.