Tsukasa, a college student, is rescued from an attack by a devil, one of many vampires that can blend in among the human population. Anzai, her savior, is a half-devil who exploits his supernatural gifts as a member of a shadowy police task force that specializes in devil-related crime in Tokyo. As Anzai continues to keep guard over Tsukasa, the two quickly forge a tentative bond—one that Anzai fears will test his iron-clad rule of never drinking human blood…
Anzai, suffering badly after a run-in with a sniper, is rescued at the last minute by a mysterious blond devil who gives him enough human blood to heal his wounds. Embarrassed by the way he lost control after tasting human blood, Anzai hides himself away from everyone, especially Tsukasa, until an incident unfolds live on broadcast TV which shines a glaring light on the devils who walk among the populace of Japan…