Mii serves as Ai's classmate and Mai's childhood friend within their manga club. Her visual design features blonde boyish short hair with a distinctive small strand sticking upward, paired with notably short stature that underscores her position as the group's least emotionally mature member.

She impulsively launches the club's activities and antics, frequently escalating them to extreme levels disapproved by others. Mii subjects Ai to bizarre scenarios and physical comedy, such as skirt-pulling attempts. Despite projecting bravery, she reveals flashes of cowardice. Her behavior consistently demonstrates a lack of common sense and a tendency to charge into situations without forethought.

Mii shares a chaotic partnership with Mai, collaborating to torment Ai through absurd and occasionally violent actions that contribute to the group's comedic sociopathy. Ai typically retaliates physically—like head strikes—while maintaining underlying friendship. Ponoka-senpai intermittently resolves Mii-caused disruptions, often employing a clay pot.

In surreal club adventures, Mii participates in battles against alien invaders, tournaments against rival clubs, and RPG-style chapter-ending confrontations. Her imagination transforms mundane activities into extraordinary events—discovering odd creatures or triggering exaggerated transformations—propelling ordinary scenarios into fantastical territory.