After finishing his part-time job, Ryou Yoake, a representative from the ReLife Research Institute, approaches Arata and persuades him to participate in a groundbreaking experiment. By living as a 17-year-old high school student for a year, Arata may be able to overcome his personal and professional obstacles and possibly land the coveted job he's been striving for.
Despite the difficulties involved in returning to high school with the knowledge and experience of an adult, Arata accepts the experiment. With no other options, he ventures into uncharted territory, facing unexpected challenges along the way.