Aestrangel the Chosen - The Aestrangel Trinity, #2

In the epic battle of Good versus Evil, there can be only one victor. To free herself from her relentless nightmares, Aestra, the fallen angel, makes a deal with the devil. But Lucifer's deals have dire consequences; robbed of the knowledge of what cast her out of heaven, Aestra cannot escape Lucifer's domain. The only way out is through. With no one left to turn to, Aestrangel reunites with her former adversary, Malek, to complete another Calling that would solidify her position in the devil's domain.
But when her power-and her feelings for Malek-intensify, this mission could end up altering the balance between Heaven, Hell, and the human world forever.