Nate, a college student, wakes up one day to find himself transformed into a vampire bat with only one hour left to live. At this critical moment, he unexpectedly forms a contract with Catherine, a prodigy from his academy. Nate soon discovers that by drinking blood, he can continuously evolve and level up—from a newborn bat pup to a high-ranking vampire lord. Determined to help Catherine win the Inter-Academy Tournament championship, the two join forces to take on the aristocratic bully Daniel. After Nate consumes Daniel's soul, he incurs the revenge of Daniel's elder brother, Cassius. Facing a powerful enemy, this unprecedented "contract beast" is about to launch a breathtaking counterattack.
