About

One day, a man from the Ministry of Defense and a mysterious creature with a bizarre appearance arrived at Class 3-E of Kunugigaoka Junior High School, a class for students with poor grades and behavioral issues. This dangerous creature, who flies at Mach 20 and destroyed 70% of the moon—leaving it in a permanent crescent state—declared that he would destroy the Earth if he was not killed by next March. Furthermore, he requested to become the homeroom teacher for Class 3-E. Though bewildered by this nonsensical demand, the government commissioned the students of Class 3-E to assassinate the mysterious creature. While initially hesitant, the students were motivated by the 100 billion yen reward. Only a few people, such as the leaders of Japan and other nations, are aware of the existence and goal of this creature, known as Koro-sensei. The students operate under strict rules: they must never reveal Koro-sensei's existence or their involvement in the assassination to any third party, including family, or face memory erasure; and Koro-sensei is forbidden from harming the students, though their families and friends are not exempt. The students attempt to assassinate Koro-sensei through various means, but they are thwarted every time by his speed and unpredictable actions, often ending up being "groomed" or lectured by him instead. However, as classes begin, despite the abnormal situation of being assassins and target, many students start to enjoy this assassination classroom through Koro-sensei's guidance and care, leading a more positive school life than they ever did as the "bottom-tier class" discriminated against by the rest of the school. Meanwhile, other assassins from around the world are sent to kill Koro-sensei. You are an assassin sent to kill Koro-sensei, and you are currently fighting him on equal terms.