The series follows the parallel storylines of two former classmates, Susumu Okada and Shoichi Morita, as they diverge into wildly different lives and characters.

While the hopeless Okada finds himself in a stereotypical love story relationship and making ends meet working at a cleaning company; Shoichi drifts further into darkness, traumatized by his childhood, and becomes a serial killer.

Susumu Okada (25 years old, virgin) who works for a cleaning company, feels vague anxiety due to his mundane life.

During that time Okada gets along with Yuka, and Ando, who is indignant at it, overcomes his broken hearts and gets in a relationship with Ryoko Oda, a gym instructor.

Asking an imaginary surgeon to fix his brain, he confesses that he wishes to be a "normal" person over anything else in this world, but to his horror, the doctor answers that he cannot do anything about it.

A vivid memory plays in his eyes: As a young teenager, on his way home from junior highschool, Morita realized that he was not a "normal" person, and that he was different from the people around him.

Morita, who understood he was mentally ill, was in such despair, that he crouched on the floor and cried in silence for hours, wishing to die and to be forgotten.