Rei Kagami (Ryosuke Yamada) is a billionaire and the CEO of the leading conglomerate company Kagami Group. He is an extremely smart inventor, who has developed revolutionary products, and is now doing research on high precision AI. When he was little, he was a curious and kind kid. As he grew up, his curiosity remained, but he became self-centered. For certain reasons, he begins to teach at a school, while hiding his identity as a billionaire and the CEO of Kagami Group. His performance as a teacher is quite poor compared to his excellent work as a CEO. He is incapable of understanding the ordinary lives of the teachers and students around him.
Mitsuhashi Yukio is a passionate PR man for a sanitary product manufacturer. A single father, he is raising his two children, a daughter in high school and a son in middle school. His daughter, Hana, has mixed feelings about her father, who suddenly became popular on social media because of a menstruation PR video he did for his company. One day, Yukio says on a variety show that he knows his daughter’s menstrual cycle, which leads to Hana running away from home because of rumors popping up at school. Can he fix the relationship with his beloved daughter? How will the two overcome this hurdle?