Moment of Tooth by Lindsay Buroker

Morgen Keller’s life has been chaotic since she inherited her grandmother’s old house—and her legacy as a witch.
Werewolves regularly attack her, familiars spy on her, and enemies she didn’t ask for keep lighting her property on fire.
Through everything, she’s been fortunate to have one steadfast ally: Amar.
The lone werewolf is a fearsome fighter, a loyal protector, and he’s sexy in nothing but a magical talisman.
Just as Morgen and Amar overcome most of her problems and officially start dating, trouble from his past arrives in town. The powerful enemy who long ago slew his parents has come to finish off the family.
As strong as Amar is, he may not be able to handle his old nemesis alone. But will he let Morgen help? And is it within her fledgling power as a witch to do so?