In ReLIFE, 27-year-old Arata Kaizaki is viewed by others as a failure after hopping between numerous jobs since leaving his first position. His circumstances shift abruptly upon meeting Ryou Yoake from the ReLife Research Institute, who presents him with a peculiar pill that guarantees a fresh beginning. Eagerly accepting the offer, Arata awakens to discover his body has reverted to that of a 17-year-old. He is informed that he has been selected for a special experiment, mandating his enrollment as a transfer student at a high school for one year. Convinced his adult perspective will provide an advantage, Arata soon realizes otherwise; on his very first day, he struggles with examinations, physical fitness tests, and updated school regulations he has forgotten. Compounding his frustration, Ryou is tasked with monitoring his progress, creating a source of constant irritation. ReLIFE centers on Arata's struggle to manage this chaotic new existence and steer clear of past errors, all while developing a deeper understanding of his classmates.