Oedo Chanko is a second-year primary school student at Furusato Girls Academy who also serves as the head of the rival organization known as Daitokai. Her appearance is notably childish, which contrasts with her position of authority and her selfish personality. This selfishness is reflected in her hobbies, primarily ordering other people around. A consequence of this demanding behavior is that she was unable to attend school while growing up, which makes her current experience of enjoying school life particularly meaningful to her.

Regarding her role in the story, Chanko is a rival to the main protagonist, Tohoku Zunko. While Daitokai originally sought to create a world that is hospitable and accepting of those who possess special powers, Chanko's personal aspirations have since evolved into a simpler desire for having fun at school. Key relationships include her rivalry with Tohoku Zunko, as well as her connections with other members of her organization such as Kansai Shinobi, who acts as a scout, and Chubu Tsurugi, who serves as a general. She also operates a large sumo robot named Genjimaru, which serves as her primary means of transportation and control.

In terms of abilities, Chanko is established as possessing the strongest power among the characters introduced in the anime film. Her primary skills involve piloting her sumo robot, Genjimaru. Furthermore, by using the fan she wears on her head, she can manipulate the actions of any person she douses with her special salt.