Kagami Rei, a newly assigned teacher to the 3rd year group of students at the private Eto Gakuen, where students with "zero motivation, zero talent, and zero future potential" are gathered. Handsome and mischievous, Mr. Kagami has an unusual teaching style that does not follow the academy's framework. In fact, he is the Chairman of the leading Japanese giant corporation Kagami with almost endless resources. Coming to this place with a hidden identity and grows with his students while facing various problems.