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.
A samurai lord has bartered away his newborn son's organs to forty-eight demons in exchange for dominance on the battlefield. Yet, the abandoned infant survives thanks to a medicine man who equips him with primitive prosthetics—lethal ones with which the wronged son will use to hunt down the multitude of demons to reclaim his body one piece at a time, before confronting his father. On his journeys the young hero encounters an orphan who claims to be the greatest thief in Japan.
Set in a fictional European country in 1924, a Japanese exchange student meets a mysterious, brilliant girl who only leaves the library to sleep. Her brother, a detective, relies on her exceptional mind to solve difficult mysteries.
The anime's setting is a fictional Japanese city named Sugomori City. One day, Noriko Sonosaki tells her classmate Katsuhira Agata, "You have been selected to be a Kiznaiver." The Kizuna System, which allows Katsuhira to share his wounds, connects him to the classmates whose lives and personalities completely differ from his. The Kizuna System is an incomplete system for the implementation of world peace that connects people through wounds. All those who are connected to this system are called Kiznaivers. When one Kiznaiver is wounded, the system divides and transmits the wound among the other Kiznaivers. Sugomori City is built on reclaimed land, but as the years go by, the city's population is decreasing. The story is set in this town where Katsuhira and the others live.
The legendary swordsmith Kiki Shikizaki created 1,000 swords in his career. The more of the swords a country owns, the higher its chances are at winning a war. When the shogun emerged victorious, he collected 988 swords, but these were merely the “practice pieces”. The last twelve swords were the crowning achievements of Kiki’s career. Each one of them is so powerful that a single man could defeat an army with it.
Togame, the shogun’s strategist, gets the order to collect these swords. At first she hired a ninja, but each of the swords’ value is so high that the entire ninja clan went rogue once they got hold of one. She then put her trust in another warrior, but he kept the sword for himself. Her final hope now is Shichika, the seventh and last student of the Kyotoryuu School.