A flower-viewing party in 1921 Tokyo is rudely disrupted by monstrous steam-powered robots, only to be swiftly defeated by a young girl wearing traditional Garb. After the devastating Demon War, Japan has once again attained peace and prosperity. Ensign Ogami Ichiro, a recent graduate of the Naval Academy, is stationed in Tokyo where his duties involve collecting tickets at the Imperial Theater. Although his tasks are mundane, he finds himself embroiled in a world filled with robots, demons, and attractive uniformed women who possess a wealth of knowledge.