Deep in a world where magic and technology have fused into one, the floating city of Vane rises as the only concentrated mass of magical engineering left on the continent. Once a place populated by demonkind, Vane now stands as a relic of a bygone era, a monument to power and mystery. At its heart lies a flying ship, a vessel referred to as the great legacy of Vane, and it is this airship that becomes the thread connecting the past to the future.

The narrative centers on a demon named Galleon, whose existence bridges two worlds. He finds himself drawn into the lives of humans who inhabit and orbit the floating city, their fates entwined with the ship and the secrets it carries. The story weaves between the legacy of the demon tribes who once filled Vane and the ambitions, fears, and hopes of the human characters who now walk its streets. Through their interactions, the manga explores themes of inheritance, coexistence, and the weight of history.

Set within the richly established universe of the classic RPG series Lunar, this manga does not simply retell the games but crafts an independent narrative using its world as a stage. The floating city itself is both a setting and a character, a place where ancient magic lingers and the boundaries between races blur. The airship serves as a catalyst, drawing together disparate lives and unlocking conflicts rooted in the city's tumultuous past. What emerges is a story of a demon named Galleon and the humans who cross his path, each carrying their own burdens as the great legacy of Vane propels them toward an uncertain future.