Saving Hinata Tachibana means changing a future Takemichi Hanagaki has already witnessed. A news report tells him that the Tokyo Manji Gang has murdered his former girlfriend and her brother. Then, moments before a train would kill him, he finds himself twelve years in the past, back in middle school and still dating Hinata.
Those school days were the peak of Takemichi's life, far removed from an adulthood spent enduring ridicule and apologizing to his younger boss. But the day he returns to also marked the start of his decline. After reliving it, he encounters Hinata's younger brother, tells him about his apparent death in the future, and urges him to protect her. When Takemichi unexpectedly returns to the present, he is alive—and the future has changed. With evidence that his actions in the past can make a difference, he resolves to travel through time to prevent Hinata's murder.
