Aya Komichi is a Japanese high school student distinguished by her long, dark hair, usually bound in high twintails though occasionally worn down. Her fair complexion frames dark blue eyes. Her standard school uniform features a navy blue sweater, pink striped bow-tie, white collared shirt, black tights, and skirt during the school year, shifting to a black sweater vest and thigh-highs in summer. Casual attire favors feminine dresses frequently accented with ribbons.

Academically diligent yet occasionally socially unaware, she possesses a reserved nature that surfaces through easily flustered reactions. She grapples with expressing emotions honestly, particularly concerning her longstanding romantic feelings for childhood friend Yōko Inokuma. This manifests in tsundere-like behavior—oscillating between sharpness and affection—especially under perceived romantic tension, such as contemplating indirect kisses or CPR scenarios. Her tendency to misinterpret social cues or voice blunt, uncomfortable truths often unintentionally disrupts group harmony.

Profound loyalty drives significant choices, like declining admission to a prestigious high school to stay with friends. She provides academic support, tutoring Yōko to prevent repeated failures and aiding Honoka Matsubara in navigating her crush on Karen. Generally composed, she reveals vulnerability about body image, acknowledging easy weight gain and experiencing distress over haircut mishaps. An admitted klutz, she rationalizes incidents like dropping Yōko’s notebook into water by asserting "klutzes are cute."

Her reliance on Yōko evolves across the series, shifting from dependency towards a desire for mutual honesty—a need she initially denies. By the manga’s conclusion and the film "Thank You!!", she attends college with Yōko and Karen, signifying sustained closeness. Relationships include respectful bonds with Shinobu Ōmiya and Alice Cartelet, connecting on intellectual and emotional levels, alongside tolerant yet distant interactions with Karen.

Notable traits encompass tone-deaf singing—dubbed "Aya-like" by peers despite competent theme song performances—and an affinity for romance stories. Her flower symbol is the Cosmos. Etymologically, her name combines "design" (綾) with the surname meaning "small road" (小路). She shares design and responsible group member role similarities with Rize Tedeza from "Is the Order a Rabbit?".