Shin'ichiro Niihama works at a job he hates, for a company with no morals, under a boss who detests him. After years of corporate abuse, one day he collapses. He wakes, only to find—he's returned to his high school self! Reunited with his once lost mother, Shin'ichiro realizes he's leapt back in time. Given a second chance at high school, he vows to do things right this time.

Most importantly, he must get close to the girl he always wished he knew better, Haruka Shijoin, to prevent the tragedy that awaits her!