The story follows Kaizaki Arata, a 27-year-old jobless man who fails at every job interviews he had after quitting his last company which he only last three months. His life changes after he met Yoake Ryou of the ReLife Research Institute, who offer him a drug that can change his appearance to 17-years-old again and to became a subject in a one-year experiment in which he began his life as a high school student again.