Shikizakura: a region in Japan where cherry blossoms are in full bloom and trees are adorned with fall leaves. A ceremony to preserve mankind is about to commence in this particular area, where the fleeting world meets the spirit world... By a weird sequence of circumstances, high school student Kakeru Miwa ends himself as an irregular member of a power suit squad entrusted with defeating Oni. These Oni possess humans and attempt to cling to the ephemeral world. Only the Yoroi power suit, which mixes ancient knowledge with cutting-edge technology, can defend people from Oni. Kakeru vows to become a hero, battling Oni and protecting Ouka Myoujin, the shrine maiden destined to save the world.