Many years into the future, advances in technology and virtual reality have changed Japan, leading to many applications in the real world, such as security, businesses, transportation and even the development of a new sport called Circlet Bout, an event played by many schools across the country.

Mixed Reality, the technology used in Circlet Bout, can be used to store data about the players, such as their academic skills, and generate weapon for matches.

By sheer coincidence, Yuka Sasaki gets involved in a Circlet Bout match against Chikage Fujimura, the best player in Japan.

Yūka gets inspired to become a CB player and, two years later, she transfers to a school in Tokyo in order to accomplish her dream.

[1] The series is directed by Hideki Tachibana and written by Nachi Kio, with animation by studio Silver Link.