Broken Angel (Book 1 in the Chronicles of a Supernatural Huntsman series)
by Alex Apostol
Kamlyn Paige joins a group of supernatural hunters to find her son's killer. When a mysterious neighbor sees her weeping on a sidewalk, he picks her up and introduces her to a new world. She goes with him to the Chamber of Darkness, and underground society, where she learns to fight evil beings and creatures as a Huntsman. But is there a traitor among them?