Billionaire Kagami Rei (Ryosuke Yamada), the CEO of Japan's largest chaebol group Kagami Group, and his secretary and bodyguard Serizawa Ichika (Haruka Kinami) work as teachers at the private Eto Academy.Served as the class teacher of Class 0, Grade 3, which had a concentration of %low-motivated, no-talented, and no-promising students.

One day, Kagami and Serizawa were walking on campus when a table fell from the sky.Then, Sho Nishitani (Rintaro Mizusawa), a student from Class 0 who came over, said one thing: there is campus bullying in the class.Kagami believes that if he can solve the problem of school bullying, it will be of great help to the research and development of AI teachers.

The next day, Kagami ordered the students in Class 0 to take out their tablets and distribute questionnaires to them.That was a questionnaire about school bullying.

Umeno Himika (Juri Uesaka)'s tablet cannot be turned on, so Serizawa gives her a spare tablet.At this time, Todo Yukimi (Ohara Azusa) raised objections to the content of the questionnaire and said that being suspected by the teacher was a blow.Facing the arrogant Yukimi, Kagami bluntly said that the focus of this questionnaire is not whether school bullying exists, but to confirm who is being bullied and who is bullying under the premise that school bullying exists.