"Keijo!!!!!!!!" is a sports manga series that revolves around the fictional competitive sport of keijo, a discipline where female athletes, known as keijo players, compete on floating platforms called "lands." The objective is to knock opponents off the platform using only their breasts or buttocks, as the use of hands and feet is prohibited. The sport is highly popular and serves as a lucrative career path for young women, offering fame and financial rewards.

The protagonist, Nozomi Kaminashi, is a former gymnast who enters the world of keijo to support her impoverished family. She enrolls at Setouchi Keijo School, a prestigious training academy for aspiring keijo players. Nozomi quickly demonstrates exceptional talent and determination, standing out among her peers. Alongside her are several key characters, including Sayaka Miyata, a skilled judo practitioner who becomes Nozomi's rival and eventual friend; Non Toyoguchi, a cheerful and physically strong athlete; and Mio Kusakai, a reserved but highly analytical player. Together, they navigate the rigorous training and intense competitions that define their journey.

The narrative follows Nozomi and her classmates as they progress through the ranks of keijo, facing increasingly challenging opponents and honing their unique techniques. Each character develops specialized moves, such as Nozomi's "Hip Escalator" and Sayaka's "Vacuum Butt Cannon," which showcase their creativity and adaptability in the sport. The story emphasizes teamwork, strategy, and perseverance, with matches often serving as dramatic set pieces that highlight the physical and mental demands of keijo.

As the series progresses, Nozomi and her friends compete in regional and national tournaments, aiming to become top-ranked keijo players. The stakes rise as they encounter formidable rivals, including elite athletes from other schools and professional leagues. The manga balances intense sports action with moments of humor and camaraderie, offering a dynamic exploration of its unique premise. Through its focus on character growth and competitive spirit, "Keijo!!!!!!!!" presents a distinctive take on the sports genre, blending athleticism with imaginative world-building.