Tonu is a high schooler with a genuine talent for art — a talent he has been systematically ignoring, alongside his belief in himself. One night, asleep, he is drawn into the realm of Ginga and encounters Ormatsu, its yokai ruler, who sustains the realm by capturing the dreams of people who have given up and transforming their souls into dog-like creatures called Mainus. Tonu has one way out: solve the Ormatsu Puzzle. That means collecting all the Mainus and mastering six elemental powers — Fire, Lightning, Water, Wood, Ice, and Wind — to defeat the realm's fifteen rulers. He has exactly eight hours before the dream state locks him inside Ginga forever.