In an endless sea of sand drifts the Mud Whale, a floating island city of clay and magic. In its chambers a small community clings to survival, cut off from its own history by the shadows of the past.

The people of the Mud Whale have fought off the forces of the Allied Empire--for now--but their only hope for continued survival is to find an ally from beyond the Sea of Sand. So when the bombastic Sir Rochalízo sails his ship alongside their island, Mayor Suou is ready and eager to befriend the stranger. But even if Rochalízo can offer asylum, they have no way to navigate their island. Until the mysterious Aíma begins unlocking the Mud Whale's secrets for Chakuro...