Koigakubo stands at 192 centimeters, his lean frame, sharp features, and thin eyes lending him an unintentionally imposing aura that once sparked rumors of yakuza ties. His short, slicked-back hair and standard black high school uniform contrast with a demeanor marked by quiet observation and introspective calm. Beneath his reserved exterior lies emotional vulnerability, revealed when he tearfully confessed his dream of pastry-making during a pivotal conversation—a passion ignited by a friend’s artistic resolve. Financial strain and self-doubt initially clouded his ambitions, but he enrolled in vocational school while funding it through construction site part-time work, often seen in a dirt-streaked apron. His culinary roots trace to childhood, where he and Sumida bonded in their elementary school cooking club. This foundation surfaces in hobbies like baking cakes for friends and whimsically naming neighborhood cats "Mezashi" and "Shishamo." A steadfast confidant, he offers measured advice, notably encouraging Yatora’s artistic talent early on. Despite his busy schedule, he maintains camaraderie with high school friends through casual gatherings discussing futures and shared laughs. His practicality and quiet sensitivity drive his evolution from uncertainty to determined pursuit of pastry arts. He navigates life on a motorcycle, his surname—combining "love" (恋) and "cave" (窪)—hinting at hidden depths. Alternate adaptations assign him the given name Shin, though his core remains unchanged: a blend of resilience, subtle warmth, and incremental growth toward his aspirations.