Ella, the eighteen-year-old eldest daughter of the earl, is held hostage by her ambitious father—who threatens her younger sister Lia to force her compliance—and offered up as a living sacrifice to the world-ending black dragon Rhaesa in exchange for a noble title. Thrown into the sacrificial abyss, Ella is instead saved by the black dragon Rhaesa, only to become his sacrificial bride, branded with a mark that belongs to him. Inside the hostile dragon temple, she endures endless scorn and humiliation. Faced with Rhaesa's domineering, possessive hold over her, she refuses to submit, biding her time for a chance to resist. On the run, she falls victim to the violent coercion of the dragon aristocrat Gale. At her breaking point, Ella cries out to Rhaesa for help. Rhaesa erupts in fury and shields her—and in that moment, something inside Ella begins to waver. On one side, her family's betrayal; on the other, the black dragon's obsessive, dangerous love. To protect her little sister, Ella struggles through oppression and hatred, refusing to be a sacrifice passed around at others' will, locked in a fated tug-of-war with the black dragon.