Iron wolf
(Book)

Burn the devil so he won't become real. Juva Sannseyr isn't just any hunter. She's one of the best. She spends her days in the barren tundra, tracking and killing wolves who have magical blood. Blood that causes addiction, wolf-sickness, and death. Blood that gives the women of her family the power to predict the future--or so they claim. Blood that sllows the wealthy to travel through portals form one world to another. Blood, it is whispered, that can make you live forever. Wolf hunting is Juva's way out of the Sannseyr home, an imposing mansion where her heart always races, where she cannot trust herself to distinguish between horrors real and imaginary. But escaping the life she was born to isn't easy, and when inexplicable tragedy strikes, Juva discovers that her family's secrets are darker and more powerful than she ever could have imagined. Since she was a little girl, Juva has tried to keep the devil at bay. But as it turns out, the devil was inside her all along... -- inside flap