Wolf's Bane — Judith Post

Reece Rutherford's brain can't process what her eyes are seeing. A full moon shines on a boy whose body is contorting and changing, sprouting fur and growing fangs. She's seen it in movies. Movies aren't real life. But then the werewolf charges her. He pins her against her SUV, his paw pressing against her chest, and she knows she's doomed until a winged man appears, as if from the sky, to save her. From that point on, her life is forever changed. The bloody scratches heal and a blood-red tattoo, in the shape of a hexagram, blazes in the flesh near her heart, revealing that she is a witch whose powers have just awakened.

Faced with a community of rogue werewolves who'd like her out of their way, a set of powers she never previously knew she had, and a brother and sister to keep safe from literal monsters--as well as their abusive step-father sleeping in the next room--Reece isn't sure her usual self-sufficiency will be enough to pull her through. Fortunately she has Damian, a stoic but sexy guardian who can help her take on her enemies and win. And maybe together they can learn that there's no point going through everything alone.