A millennium after human extinction, vampires and werewolves share dominion. Vampire First Baron Knox and werewolf champion Aurora are sworn enemies—and secret lovers. When the Werewolf King enacts the 'Pure Blood Decree' branding Aurora's mother inferior, Aurora must win the Twin Moons Festival to claim the wish-granting 'Twin Moons Heart' and save her. To help him, Knox performs the forbidden Blood Clan ritual 'Shared Life,' allowing Aurora to wield vampire power.