Bone crossed - Patricia Briggs

Car mechanic and sometime shapeshifter Mercy Thompson has learned, the hard way, why her race was almost exterminated. When European vampires immigrated to North America, they found Mercy's people had a hidden talent - for vampire slaying. Unfortunately for Mercy, the queen of the local vampire seethe has discovered her true identity.

She's also furious when she learns Mercy has crossed her and killed one of her vampires. Mercy may be protected from direct reprisals by the werewolf pack (and her interesting relationship with its Alpha), but that just means Marsilia will come after Mercy some other way. So Mercy had better prepare to watch her back.