Mito Shiromaru is a 16-year-old second-year high school student affiliated with the Gekidan Denki theatrical troupe, born and raised in Akihabara. Her complex family environment fostered a quiet, passive, and introverted personality marked by social anxiety and possible PTSD from parental abuse. This history initially hindered friendship-building, eroded her self-confidence, and caused hesitation toward new activities or routine tasks.

Her life shifted after meeting Iroha Senju in high school. Iroha became her first friend, earning Mito’s complete trust. Inspired by Iroha’s interests, Mito embraced cosplay and anime viewing. She followed Iroha to audition for Gekidan Denki, joining primarily due to the invitation. Since entering the troupe, her confidence has steadily grown with support from Iroha and fellow members.

Mito resides with her grandparents, who operate a restaurant. Assisting them cultivated her cooking skills, and she frequently prepares lunchboxes for Iroha.

In acting, Mito possesses a unique "Sense" ability—"Awakening Ability" (才色兼備の目覚め). When deeply immersed in a role, she temporarily accesses and utilizes that character’s talents, effectively becoming the role. This requires thorough prior understanding of the play’s narrative and the character’s traits. The ability first manifested during Gekidan Denki’s entrance exam, revealing her latent potential despite no initial acting ambition. During film viewings, this trait may trigger unconscious mimicry, such as reenacting zombie attacks, though she typically returns to normal swiftly.

Mito has shoulder-length fluffy brown hair styled in two small buns with V-shaped bangs, accented by two four-leaf clover hairpins. Her gentle green eyes complement her typical attire: a high school uniform worn with an open jacket, white turtleneck, and ankle socks.

Her hobbies include cosplay, anime viewing, and film watching—activities predominantly shared with Iroha that originated from their friendship and function as stress coping mechanisms.