This is an anime adaptation of an original story written by Matsui Yuusei.

One day the shape of the moon became a crescent moon. More than half of the moon was destroyed. A mysterious organism, which looked like an octopus, came to Kunugigaoka Junior High School as the “homeroom teacher” for Class 3-E. It was the culprit for the destruction of the moon. Someone from the Ministry of Defense requested that the organism be assassinated by 3-E. The students can’t kill him no matter how hard they try, so they name him Korosense. He was a very good teacher and worked very hard to improve his students’ grades. And the bond between teacher and student has deepened.

Can they kill a teacher before they graduate? I’d like you to see it.

This story gives us the strength to overcome adversity; the students in 3-E were constantly being told that they were not good enough by those around them.And they accepted it.But the teacher teaches them many things to turn that situation around.They work hard to respond to their teacher’s efforts and overcome adversity.This gives me courage.