Noroware Kyoushitsu ~Kounai Itsudemo Dokodemo Yaranakucha?!~

One day in a classroom, when students were having their belongings inspected many erotic objects were found in their bags, and suddenly an erotic video started playing on the class TV. There are suspicions about whether this is the work of a god, spirit, or monster that teaches the goodness of eroticism to students. The class president, Minami, is tasked with organizing the erotic objects and is interrupted by a classmate, Anri, who shows interest in the objects. Minami eventually collapses from exhaustion.
The next day, when she confronted some boys about their strange behavior, it turned out that they all had a video of Manami masturbating with an erotic toy from the day before. In the video, Manami smiles lasciviously and says, "P-Please tell me how many times you came using this video tomorrow..." Manami denies any involvement and claims that she has nothing to do with the video.
Anri starts deleting a video from a boy's phone when another boy refuses and escapes, only to be swallowed up by darkness. The classroom panics and an erotic video appears on the TV, causing the teacher, Hinano, to remember a similar incident from her school days. She believes the class is cursed and that they must engage in sexual activities every day. Those who try to run away will be swallowed by darkness and confined in a space of humiliation. The boys seem to enjoy the situation, while Manami's cries are in vain as the debauched school life begins.