An Inheritance of Curses by Dee J. Holmes

Driven by a lust for powerful blood, the first LeFey plunged the Four Houses of Magic into a century of conflict. Survivors of the Great War, desperate to repair their tattered worlds, signed a treaty banning any contact between the Houses of fae, werewolf, vampire and witch. And for over a thousand years that treaty has held strong…
Haunted by the dark talents she once embraced, Rose LeFey is determined to confront her manipulative aunt and prove she’s finished with blood magic. Instead, she finds a basement full of prisoners and a false-mate bond with an insanely attractive, and utterly forbidden, werewolf.
As lust tears into her hard-earned self-control, Rose realizes the werewolf was bait. Her aunt wants to unleash war on the magical Houses and humans alike—with Rose at her side. To stop that from happening, Rose must deny both her own deadly powers and the temptation to turn the false mate-bond real.