Devastated at the death of her four-year-old daughter, a grieving middle school teacher is horrified to discover that her students aren't as innocent as she thinks.

Keisuke Miyahara oversleeps on the day of his entrance exam for Tokyo University. To postpone the exam starting time, Keisuke Miyahara sends an email to the school warning of a bomb. His plan works and he is able to take his exam and passes. On the day of his entrance ceremony, a man named Hiroshi Tanaka appears in front of Keisuke Miyahara and threatens him.

A story about the disappearance of Kirishima, a star athlete of the volleyball club, and how his disappearance affects every person in school.