High above Earth, invisible to human eyes, float the Heavens—a cluster of island kingdoms kept aloft by the magic of their godlike residents. The mysterious energy source called Akuto makes this magic possible, but it is rapidly depleting. To address this energy crisis, most Heavens kingdoms agree to limit their Akuto usage to the bare minimum needed for survival, with the exception of the Magical Kingdom. Its ruler, King Munto, is convinced that Akuto can be restored if he journeys to Earth and finds a mysterious girl revealed to him by a seer. As Munto embarks on this perilous trip, the other kingdoms move to destroy the Magical Kingdom and seize the remaining Akuto for their own use. On Earth, Yumemi Hidaka faces her own troubles. She sees floating islands in the sky that no one else can perceive. Although her best friend Ichiko Ono believes her, Yumemi questions whether she is losing her mind. When Munto suddenly appears before her, she dismisses him as a mere hallucination. Her primary concern is her 13-year-old friend Suzume Imamura, who is trying to run away with her delinquent boyfriend. As the Magical Kingdom approaches the brink of falling from the sky, Munto's mission to save both the Heavens and Earth becomes increasingly desperate.