Zuo Yi, a transmigrator, fought and struggled in the world of Sadya for three hundred years. During his fight with the Abyssal Lord, Saur, he was sent back to the blue planet.To his immense shock, he had somehow gained an adorable four-year-old daughter! Zuo Yi, who has long been tired of the life of a knight, gradually interacts with the blue planet's various forces and ultimately resolves the global crisis—all for the sake of building an ideal world for his precious child.