Bullet Witch

In the wake of multiple natural disasters culminating in a demon invasion in 2007, Earth has become a wasteland, and by the year 2013 humanity is on the brink of extinction. Alicia Claus, a witch guided by a demonic power dubbed the "Darkness", enters a near-deserted American city. During her time there, she and the resistance are forced to flee from Omega—a powerful demon immune to magic and gunfire—and Maxwell asks for her aid in saving humanity. (wiki)