Hideyoshino is an average girl who always seems to find trouble wherever she goes. One day, Hideyoshino notice a blue light coming from inside a local Shrine and see a mysterious person performing a magic spell. In a stroke of bad luck, Hideyoshino trips and crashes into the shrine, prompting the magic spell to spiral out of control and sends her back in time to the Sengoku Era. But Hideyoshino realizes that everyone in the world is female. She then decides to help Oda Nobunaga find the Crimson Armor which is said to allow the person wearing the armor to conquer all of Japan.