Dog Days takes place in the world of Flonyard, an alternate world where its inhabitants look like humans but with animal ears. When Cinque Izumi suddenly gets summoned to this alternate world he is appointed as a Hero. How will he lead his life and interact with the various characters in this new world?
Three of the warriors return to Flonyard. The stage happens to be during autumn. A mysterious girl, Sharu, who's not yet been known as enemy or ally joins their story too and creates more riot than ever!