To escape from the sudden societal pressure of winning four billion yen from a lottery, Kazura Shino flees to his father's spare residence deep in the mountains. In awe, he takes a tour around the house and discovers a secret corridor longer than the building itself. As he follows it, Kazura finds himself in a village belonging to another world. The village, called Grisea, is in extreme poverty due to the detrimental effects of a recent war. Feeling sympathetic toward the locals, Kazura uses his newfound riches to provide them with food and medicine, along with funding improvements for the village. With his help, the small town gradually begins to flourish. However, Kazura's arrival in Grisea sparks an old legend concerning Greysior, a benevolent god of harvest who disappeared due to the horrendous consequences he suffered after assisting the village. In addition, how Kazura entered this world resembles Greysior’s story. Now that the residents of Grisea believe their god has "returned," it is only a matter of time before surrounding territories discover Kazura and seek his assistance. [Written by MAL Rewrite]