Set in Hinomoto, a fictitious version of Japan where railway travel was formerly the primary mode of transportation. Each locomotive was outfitted with a humanoid control module known as Raillord, which assisted the train operator. Many train lines, however, had been abandoned due to the growing popularity of "aerocrafts," a safe and convenient airborne means of transportation. As a result, their accompanying railways likewise fell asleep. Soutetsu had lost his entire family in a train catastrophe and was adopted by the Migita family, who owns a shochu brewery in Ohitoyo. He returned to his hometown to protect it from the probable water contamination that would occur if the plan to establish an aircraft manufacturing was allowed.