Marumi was accepted into her high school through her Kyudo (Japanese Archery) skills, but recently, her growing breasts are getting in the way. Now, she has been forced to quit Kyudo and is now on the brink of being kicked out of her high school due to her not so stellar grades. Her teacher recommended her to a club known as "Rikijo," a female sumo wrestling club. Will Marumi be able to keep up with this new club?