According to the tale, Muto shin (deity with clear roots in the Korean peninsula) had asked his wealthy younger brother, Shorai, for the place to sleep during his journey and had been refused; Muto shin asked his poor brother, Somin shorai as well, and Somin Shorai treated him even in a poor way.
すなわち、旅の途中で宿を乞うた武塔神（むとうしん）を裕福な弟の将来（『備後国風土記』では「或本作巨旦將來也」とあり、巨旦将来　こたんしょうらいとされる）は断り、貧しい兄・蘇民将来は粗末ながらもてなした。