Purgatory

She is the toy of angels, trapped in a world where there is only good and evil, only Etherals and Malignants. Kisos, a human girl who has lost everything she once had as a mortal, has only one job: to kill the demons. But sometimes the evil she fights does not overcome the evil within her and she learns what it means to be human and what it means to be neither divine or damned in a battle between hell and heaven.