Mikoto Urabe, the enigmatic protagonist of Mysterious Girlfriend X, is a teenage girl of average height with a slender build. Her most defining physical characteristic is her messy, untidy black hair that falls over her face, entirely obscuring her eyes from view to enhance her gloomy and detached demeanor. In this image, she wears her standard summer school uniform, which consists of a short-sleeved white sailor shirt featuring dark blue collar cuffs and a prominent oversized red bow at the chest. This top is paired with a pleated dark blue skirt, mid-calf white socks, and classic black school loafers. She balances her look by holding a brown school briefcase while concealing her iconic "panty scissors" out of sight beneath her skirt.

depicted as a relatively ordinary high school student. Visually, he has a slender, athletic build, a somewhat rounded face, pale skin, large expressive eyes with dark brown pupils, and neat, black hair cut into short bangs that frame his forehead. His typical school uniform consists of a short-sleeved, button-up white shirt worn open over a reddish-orange undershirt, paired with loose-fitting dark navy blue trousers. To complete his everyday student look, he wears beige sneakers featuring a distinct white toe cap and purple laces, and carries a small, vibrant green backpack with black straps slung over his shoulders.