Unable to remember the past, high school senior Saya Otonashi must rediscover her destiny in order to defeat the chiropteran vampires that threaten her loved ones' existence.
- Genre: Animation, Sci-Fi & Fantasy, Action & Adventure
- Studio: TBS
- Keyword: amnesia, monster, swordplay, vampire, supernatural, secret organization, gore, horror, rivalry, betrayal, conspiracy, disaster, gunfight, epidemic, catholic school, military, anti war, dark fantasy, angst, shounen, anime, reverse harem
- Cast: Eri Kitamura, Katsuyuki Konishi, Hiroyuki Yoshino, Akiko Yajima, Hochu Otsuka, Jurota Kosugi