Is That the Extent of Your Service?

Ryouta Asagiri unknowingly wanders into a country of vampires that had just recently become independent from Japan. There he meets a pretty little vampire girl named Shiren Fuyukura, who suddenly questions him and bites him, later to claim that he has become her "Minion." He soon finds out that he is unable to leave this country of vampires (The Sacred Blood Empire) and thus decides to comply to the vampire girl in becoming her "Minion."