On his eighteenth birthday, privileged Leo learns his parents once signed a blood pact with vampire Wayne, borrowing twenty years of lifespan to save his premature life. With the contract expired, Leo goes to Wayne’s mansion to repay the debt as a servant. They fall in love, yet Wayne keeps his distance, haunted by losing a past lover. Leo sacrifices himself shielding Wayne from enemies. Grief-stricken, Wayne vows to find his reincarnation. Fifteen years later, he meets Leo’s new self at a university lecture. Though the boy has no memories, he keeps dreaming of their past. Free of blood debts this time, Leo signs a voluntary oath to stay by Wayne’s side forever.
