Welcome to Blood Night City, a place where vampires seeking blood and humans seeking blood buyers gather. Sotetsu, born with undesirable blood, works at the Blood Control Bureau, an organization that cracks down on vampires' illegal activity. One day he encounters a mysterious vampire named Mozu who calls himself a gourmand and seems quite interested in Sotetsu. With their fates bound in blood, a suspensful battle of courtship and salvation awaits!