Set in Hiroshima prefecture. Kisaragi Hazime and Akahata Satomi work in the Mihara City Hall and are in charge of the official city mascot called Yassadaru Man. However, the popularity of the mascot is going down and was ranked 263th nationwide in the Yuru-chara Grand Prix. One evening, Hazime meets Isoya Yuna, a fan of Yassadaru Man, who would start working with them in managing the mascot. Hazime falls in love with Yuna, and start the journey of reviving Yassadaru Man popularity.