Due to a traumatic experience in kindergarten where his beloved teacher rejected him and married another man, high school student Makoto Saiki has developed a deep-seated distrust of all people called sensei. He believes teachers are untrustworthy and keeps his distance from them. However, his life takes an unexpected turn when he is called to the staff room after school by Maka Fujiki, the most beautiful and popular teacher at his school. To his utter shock, the 28-year-old English teacher looks him directly in the eyes and confesses, I love you. Without any explanation for her feelings, she declares that until Makoto says he loves her back, she will continue to pursue him relentlessly.

Thus begins a forbidden relationship between a student and his teacher, a romance that is absolutely off-limits. Maka uses her position to summon Makoto for what she calls guidance counseling after school, but these sessions blur every possible line. They watch adult videos together, engage in excessive skinship, go on dates, and gradually push the boundaries of what is acceptable between an educator and her pupil. As time passes, Makoto finds himself becoming increasingly conscious of Maka not just as a sensei, but as a woman. Yet a constant shadow hangs over their interactions if they officially become a couple, Maka would be forced to resign from her teaching position.

The story is set in a typical Japanese high school and follows the push-and-pull dynamic between a reluctant, teacher-hating student and an aggressively forward female teacher who refuses to take no for an answer. The narrative tension comes from whether Makoto can overcome his past trauma and whether the two can navigate a relationship that society strictly forbids.

Several narrative arcs develop over the course of the nine-volume series. The initial arc establishes Maka's relentless pursuit and Makoto's stubborn resistance as he tries to understand why this popular teacher has chosen him. As other female characters are introduced, including Makoto's sister and a young-looking rival who also confesses to him, the story expands into a romantic comedy with harem elements. These additional heroines create competition and complicate Makoto's growing feelings for Maka. The middle volumes focus on deepening the secret relationship, with the couple hiding their interactions from other students and faculty while struggling with the risk of exposure. The final arc builds toward graduation, where Makoto must make a definitive choice about his future with Maka. The series concludes with the graduation examinations, bringing the forbidden love story to a resolution after multiple volumes of tension, comedy, and romantic development.