Synopsis

This work is a school horror story set just before summer vacation, where high school students are participating in a secretly popular forbidden game.
What begins as a harmless bit of fun soon distorts the students’ everyday lives, eventually leading to a disturbing incident on campus. Taking the situation seriously, the school brings in psychologist Hirase Koharu to counsel the students who witnessed the incident. However, one of the students who took part in the game turns out to be Koharu’s younger sister, Nanami.
As the truth unfolds, one by one, the students become entangled in a series of terrifying supernatural events.