The first 12 episodes of the anime set in a post-apocalyptic world where humans do battle with vampires. A man-made virus has devastated Earth, leaving only the youth of society to fight the undead who have emerged to enslave those who remain. Yuichiro (voice of Miyu Irino) manages to escape vampire clutches and trains to become part of the elite 'Moon Demon Company'. Along with his companions, he must fight to save the human race and rescue his friend Mikaela (Kensho Ono), who has been captured and turned into a vampire. The episodes are: 'The World of Blood Legacy', 'Humanity After the Fall', 'The Demon in Your Heart', 'Vampire Mikaela', 'Black Demons Contract', 'New Family', 'Mitsuba's Team', 'First Extermination', 'Vampire Attack', 'Results of the Choice', 'Reunion of Childhood Friends' and 'Everyone Is a Sinner'.