Before she was even born, Nyx was sold by her brutish father to the demon Gentle Lord that rules over Arcadia. He made a bet with the Gentle Lord, and lost, like many other foolish people in Arcadia. It has suffered for almost 1000 years under the Gentle Lord's rule and the demons that escape his castle from time to time. When a person lays eyes on a demon they either die or go insane. So things don't look too good for Nyx. She arrives at his castle, ready to kill him, as she has been trained, but things of course don't go according to plan.
Nyx is not the average female heroine. She is strong and make mistakes, but also owns up to the mistakes. I liked how cruel she was, and how realistic she acted to her situation. She wavers between fear, happiness, hope, guilt, and shame. When I first picked it up I thought it would just be a Beauty and the Beast retelling, which would have been awesome in and of itself, but it was so much more. There are nods to Greek mythology (Cupid and Psyche) as well as Rumpelstiltskin and Bluebeard (google it and cry). There were a few moments in the book where I was screaming out loud, and whenever that happens it’s a beautiful thing.