When the skies above their village begin to rain down ash, brother and sister Akira and Yui use their unique ability to dance with the ash, creating temporary portals to other worlds. Their village is on the verge of destruction due to an approaching storm cloud, and only they can save it by reaching the sacred mountain where the Spirit of Ash, who controls the skies, resides. Along the way, they face dangers, meet allies from other worlds, and uncover an ancient secret tied to their family and past. But what is more important — saving their world or discovering their true destiny?