Mikuru Bandō serves as leader of the idol unit Tetrarkhia within the series while attending her third year of middle school. She possesses slanted reddish eyes and short brunette hair reaching mid-neck length, featuring stray strands and two gold streaks. Her bangs sweep predominantly left with a split at the right corner, partially obscured by longer forelocks. Her coordinated unit outfit includes mismatched stockings: one striped thigh-high and the other black, ending inches above the knee. Her personal style blends cool and feminine elements like collars, miniskirts, and jackets or parkas.

Mikuru exhibits a strong, proactive personality in social interactions, consistent with her leadership role, yet feels embarrassment about her given name, which occasionally draws teasing from unit mates. Her surname Bandō incorporates the character for "east" (東), aligning with Tetrarkhia’s naming theme. The name Mikuru combines the characters for "beautiful" (美), "long time" (久), and "dragon" (龍), referencing the Azure Dragon (青龍) as an eastern symbol in traditional cosmology.