Takeshi is a high school student grappling with significant family instability. His father's frequent absence due to work obligations forces multiple family relocations, contributing to his mother Ikuyo's loneliness and leading her into an affair with a delivery man named Ken. Takeshi is aware of this situation but remains preoccupied with his own concerns.

Academically, Takeshi attends Asunaro Public School, preparing for university entrance exams to meet his mother's expectations. He struggles to concentrate, his focus persistently derailed by vivid erotic fantasies. His studies are frequently interrupted, particularly by his collection of erotic magazines, which serve as an escape from academic pressures.

Takeshi is intensely preoccupied with sexual experiences, harboring an urgent desire to lose his virginity. Fantasies involving women of various ages dominate his daily thoughts, making it difficult to focus on responsibilities or long-term goals.

A pivotal moment occurs when his dog Momoe leads him to an estate where he encounters Saori (also called Sayuri), a young woman who shares his urgency regarding sexual experiences. The interaction between their dogs, Momoe and Tomokatsu, ignites a sexual encounter between Takeshi and Saori, fulfilling his wish to lose his virginity. This event marks a significant, though singular, development in his personal experiences.