Living a dull life as an ordinary teacher, the protagonist finds himself drawn to Natsu Tojo, a student captivated by his apathetic demeanor. One afternoon after school, she invites him to a love hotel, declaring, "I'll change you, sensei." There, she crosses the boundary between student and teacher, aggressively taking control of his body. Stimulated at his prostate, he moans helplessly as he reaches a dry orgasm. Then, she demonstrates female ejaculation training with another man, leaving the protagonist crouched in ecstasy as his anus is pleasured. This unique sensation, something only she can awaken in him, gradually pulls him deeper into her world. Ultimately, they engage in a reverse anal-fucking threesome, where he learns from his student the pleasure of climaxing like a girl. Through these encounters, their bond grows increasingly intense.