Bad Mouth by Angela McCallister
After her ex-husband's obsession with vampires, Valerie Craig is on a mission to stop transformations. Of all vampires, Kade Rollins is the worst of the worst, but when multiple murders plague Seattle, Val is forced to enlist his aid. Kade's crude wit and seductive nature attract her like no other, but she can't ignore his violence toward his human servants, no matter her yearning to forget.
She's torn when she learns Kade may be behind the murders. Val's worked hard to protect humans from vampires, but the truth surrounding the murders could ignite a bloody battle between their races, one humans are sure to lose. Someone is pulling strings to build a vampire army and spark the war—setting Kade up to kick it off. But if she trusts the vampire prince, she risks her job, her integrity, and her heart if he betrays her as all the men in her life have.