It is the year 300 of the Divine Era. The world inside the Shinju where all Heroes and Mikos were summoned from all ages during the crisis of the Shinju. They gathered in Sanshuu Middle School Hero Club and have transformed it into a large family with a total of 27 members. The club president, Inubouzaki Fuu who gathered these powerful friends together, announces the development of the long-awaited Hero Club Udon.