Days of Blood & Starlight (Daughter of Smoke and Bone) by Laini Taylor

Description

Once upon a time, an angel and a devil fell in love and dared to imagine a world free of bloodshed and war.
This is not that world.
Ar student and monster's apprentice Karou finally has the answers she has always sought. She knows who she is–and what she is. But with this knowledge comes another truth she would give anything to undo: She loved the enemy and he betrayed her, and a world suffered for it.
In this stunning sequel to the highly acclaimed Daughter of Smoke & Bone, Karou must decide how far she'll go to avenge her people. Filled with heartbreak and beauty, secrets and impossible choices, Days of Blood & Starlight finds Karou and Akiva on opposing sides as an age-old war stirs back to life.
While Karou and her allies build a monstrous army in a land of dust and starlight, Akiva wages a different sort of battle: a battle for redemption. For hope.
But can any hope be salvaged from the ashes of their broken dream?