Introduction: Eluvie has no idea what she is. Once a week, her captors drain her blood; once a day, they perform their torturous ritual to keep her bound. She endures her captivity by rote, too weak to escape, yet too resilient to surrender.Then she learns of another of her kind鈥攁nd vows to protect him at any cost. But while some prisons have walls to climb, others are as vast as the sky above....