Wataru Morishita attends the Osei Gakuen, which is based on the principle of scholastic ability. During the same lunch break as usual,
Wataru is deeply depressed when he receives a report of his marriage from his deputy teacher, Miwa Shirakawa, who was secretly thinking about it.
At that time, an alarm sound is heard from the smartphone in the pocket, and the mysterious app “Sai * app” is displayed on the screen.
Wataru gets an app with a powerful effect and involves Kyoko Tsukishima, who is in charge of it.
