Players trapped in a role-playing game's virtual world face real-life death as they try to escape. However, if they die in the game, they die in real life. Their struggle for survival starts now...
Ken Kaneki is a bookworm college student who meets a girl names Rize at a cafe he frequents. They're the same age and have the same interests, so they quickly become close. Little does Kaneki know that Rize is a ghoul – a kind of monster that lives by hunting and devouring human flesh. When part of her special organ – "the red child" – is transplanted into Kaneki, he becomes a ghoul himself, trapped in a warped world where humans are not the top of the food chain.
Although admired at school for her amiability and academic prowess, high school student Kyouko Hori has been hiding another side of her. With her parents often away from home due to work, Hori has to look after her younger brother and do the housework, leaving no chance to socialize away from school.Meanwhile, Izumi Miyamura is seen as a brooding, glasses-wearing otaku. However, in reality, he is a gentle person inept at studying. Furthermore, he has nine piercings hidden behind his long hair and a tattoo along his back and left shoulder.By sheer chance, Hori and Miyamura cross paths outside of school—neither looking as the other expects. These seemingly polar opposites become friends, sharing with each other a side they have never shown to anyone else.
After moving into the quiet town of Hinamizawa, Maebara Keiichi spends his days blissfully in school often playing games with his local friends. However, appearances can be deceiving. One fateful day, Keiichi stumbles upon news of a murder that had occurred in Hinamizawa. From this point on, horrific events unfold in front of Keiichi, as he soon learns his close friends may not be all that they seem. Based on the amateur mystery game by 07th Expansion, the story is told in a series of different scenarios.
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.