Over the years, the reputation of women's soccer in Japan has been gradually waning. Despite this rather bleak scenario, there are still some schools with teams trying to keep the sport alive. With that, glimmers of hope are starting to appear. Having played for the boys' soccer club when she was in middle school, Nozomi Onda's skills are nothing less than prodigious. Because of this, she thinks that playing soccer with fellow girls would only drag her down. She is only motivated to play her best when facing those she deems worthy opponents. Meanwhile, Sumire Suou is a promising rookie with exceptional talent—a talent hindered by a team that cannot keep up with her abilities. Onda, convinced by her former coach to join a girls' soccer club, and Suou, accompanied by her close friend and rival Midori Soshizaki, cross paths as members of the Warabi Seinan High School's girls' soccer team. In this new field, both girls begin to display their full potential and skills. Along with their teammates, each of their steps, kicks, and goals will grant them victory—and perhaps also ensure that the sport begins its journey back into the spotlight.

High schooler Hayase Nagatoro loves to spend her free time doing one thing, and that is to bully her Senpai! After Nagatoro and her friends stumble upon the aspiring artist's drawings, they find enjoyment in mercilessly bullying the timid Senpai. Nagatoro resolves to continue her cruel game and visits him daily so that she can force Senpai into doing whatever interests her at the time, especially if it makes him uncomfortable. Slightly aroused by and somewhat fearful of Nagatoro, Senpai is constantly roped into her antics as his interests, hobbies, appearance, and even personality are used against him as she entertains herself at his expense. As time goes on, Senpai realizes that he doesn't dislike Nagatoro's presence, and the two of them develop an uneasy friendship as one patiently puts up with the antics of the other.

As technology advanced, humanity gradually colonized the entire solar system, occupying planetary facilities from Mercury to Pluto. This results in a large-scale athletic tournament, the "Daiundoukai," where several aspiring female athletes from all around the solar system compete. The winner of the tournament is crowned the "Cosmo Beauty," obtaining a queenlike status. When outgoing potato farmer Kanata Akehoshi was a child, she witnessed a meteor-like object falling from the sky, crashing in a nearby forest. When she came to investigate the wreckage, she saw a damaged spaceship and a girl who seemed to have been in it weakened by the impact. The girl gave Kanata two wristbands, alongside a request that Kanata join the Daiundoukai and become the Cosmo Beauty. Kanata obliged, but before she could ask for the girl's name, she mysteriously disappeared—leaving nothing,not even the crater caused by the crash. Since then, Kanata has devoted herself to training, aiming to fulfill her promise. After winning the qualifying round to represent the planet Earth, Kanata goes to the University Satellite—an institution where she and other candidates study to prepare themselves for the upcoming competition. There, she meets and befriends her fellow competitors, helping them get along with each other to perform better in the games. As Kanata grows closer to the coveted title, so do her chances of meeting the girl who changed her fate—and she discovers an underlying mystery behind the Daiundoukai along the way.

Episode 0 of Seikaisuru Kado premiering on Amazon Prime.