Ancient Japan faces an assault from formidable entities known as "Kamikui," leaving it to the "Oni" and his group of eight beautiful female warriors to halt them. Each of these girls possesses distinct skills, abilities, and personalities. They join forces with the Oni, Jin, to counter the miasma of darkness spreading across Japan. Onigiri chronicles the adventures of Jin and his lively companions as they deepen their bonds and repel the demonic invasion.