What Sleeps Within the Cove: Of Flesh & Bone, Book Four (Of Flesh & Bone #4)

"Offering Mab my bound allegiance was the only way to save Caldris's life--the only bargain I could make to keep us both from the Void. After cruelly murdering the King of Summer, her own brother, Mab became unhinged and there was no telling what she would do. Caldris is safe for now because of my sacrifice, but at a cost. Queen Mab only wants one thing from me. Mab has demanded a tribute--a snake from the crown of Medusa. Navigating through the horrors of Tartarus, I must pass the Trials of the Five Rivers to prove my worth to the primordials and steal the unthinkable. All without my magic. To survive, I must discover who I am--who I'm fated to be. Human, and Fae, and something--other. Embracing all the sides of magic, light and dark, is the only way to escape Tartarus and get back to Caldris. I will save him, the Fae, and the humans from Mab"--