The last huntress
(Book)

"Alice Daniels has a problem. Her reflection keeps misbehaving when she looks in the mirror--and the longer she ignores it, the harder it tries to get her attention. On her eighteenth birthday, she learns why: she is a huntress, someone gifted with the power to enter mirrors and the magical world that exists beyond. But with this power comes immense responsibility, for in the Mirror Realm lurks an evil that has infected the human race for centuries: demons. It is up to her and her three huntress sisters--with the help of one handsome and overbearing protector--to hunt and banish this evil one demon at a time, thereby keeping the chaos in check. But when an ancient god pays Alice a visit that turns deadly, it is clear the Mirror Realm is more than it seems, and she soon finds herself in a race against time to save the life--and soul--of the one man the gods are determined to never let her have."--Amazon website.