Cinque Izumi is summoned to an alternate world by the Princess Millhiore in order to defend Millhiore's country from the neighboring kingdom of Garrett.

Following his wild adventure in the Flonyard, Cinque is summoned back once again! However, this time he is joined with childhood friend Rebecca and cousin Nanami to become Galette's Hero as the war wages on the battlefield and in desperate need for an end to the fighting…

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!