Kentaro Sanada is a 40-year-old man who spent 17 years as a Sales Department Manager in an advertising agency before its sudden bankruptcy left him unemployed. Despite extensive job searching, he struggled fruitlessly to find new employment. As his unemployment benefits neared expiration and financial instability loomed, he maintained his characteristically passive approach to life, having never exhibited deep passion for any pursuit.

During his job hunt, he applied to Manpuku Talent Production, unaware it involved an idol audition. He mistakenly attended what he believed was a standard training session, only to discover he had been selected for Eternal Boys – a new idol group composed entirely of middle-aged men. His initial reaction to this unexpected career shift was shock and disbelief.

Within Eternal Boys, Kentaro joined five other members in their late 30s to 40s, each bringing diverse backgrounds and life experiences. The group aimed to overcome societal barriers surrounding age and physical ability within the idol industry. Kentaro embodied the perspective of an ordinary salaryman thrust into this unconventional profession, contrasting sharply with members possessing prior entertainment experience. Throughout their activities, he gradually adapted to the demands of idol life—performances and public appearances—while navigating personal insecurities rooted in his professional setbacks. His journey involved adjusting to this new identity and collaborating with the group to demonstrate that individuals could forge new creative paths regardless of age.