Daina Nariyuki is an English teacher at a school with liberal rules. He possesses a charming and attractive appearance, making him popular with female staff and students. Aware of his appeal, he deliberately wields his charm to pursue romantic relationships with multiple female students: Lisa, Fumiko, Naoki, and Mimiko. He leverages the school's permissive environment, which allows considerable personal freedom provided activities avoid attracting administration attention during infrequent inspections.

He confidently operates, viewing his methods as honorable compared to his rival, Dean Onikuma. Onikuma employs blackmail and coercion to force the same students into sexual games. This creates a conflict where Daina positions himself as the students' potential protector against the dean's sinister plans. This rivalry drives Daina to intervene and "save" the students from Onikuma's exploitation.

Additionally, Daina expresses romantic interest in his new assistant, Mayu, indicating his pursuits extend beyond students to colleagues. His overarching goal involves navigating the conflict with Onikuma while attempting to establish relationships with all these women simultaneously.