Sanae is the captain of the karate team. In the year previous to the events of the series, she went to the National Karate Competition and placed second, raising the near-defunct karate team into recognition. She has declared an unofficial war on the MMA club and has convinced the other karate team members to do the same. She and Natsuo were childhood friends, but ever since Natsuo left the karate team on the basis that no one on the team was good enough, she has acted coldly toward Natsuo. This feeling accentuated after she saw Natsuo fighting with Yuzuko and drew the conclusion that Natsuo had joined the MMA club.