In a post-apocalyptic world of vampires vs. humans, Yuichiro brings vengeance upon his vampire overlords! After trumpets of the apocalypse proclaim the fall of humanity, vampires arise from the shadows to rule the earth. Yuichiro wants just one thing—to get revenge by killing each and every vampire. A vampire attack reunites childhood friends Yuichiro and Mika, though they now face each other from opposing sides of the battlefield. Mika begs Yuichiro to forget about the conflict between humans and vampires and escape with him, but Yuichiro is unable to abandon his new friends. Then, everything changes when Yuichiro suddenly transforms into a monstrous being with one seraphic wing!