The Hollow Heart (Forgotten Gods, Book #2) by Marie Rutkoski
Intrigue, romance, and magic abound in The Hollow Heart, the heart-stopping conclusion to Marie Rutkoski's Forgotten Gods duology.
At the end of The Midnight Lie, Nirrim offered up her heart to the god of thieves in order to restore her people's memories of their city's history. The Half Kith who once lived imprisoned behind the city's wall now realize that many among them are powerful. Meanwhile, the person Nirrim once loved most, Sid, has returned to her home country of Herran, where she must navigate the politics of being a rogue princess who has finally agreed to do her duty.
In the Herrani court, rumors begin to grow of a new threat rising across the sea, of magic unleashed on the world, and of a cruel, black-haired queen who can push false memories into your mind, so that you believe your dearest friends to be your enemies.
Sid doesn't know that this queen is Nirrim, who seeks her revenge against a world that has wronged her. Can Sid save Nirrim from herself? Does Nirrim even want to be saved? As blood is shed and war begins, Sid and Nirrim find that it might not matter what they want...for the gods have their own plans.