Komari Koshigaya is a second-year middle school student at Asahigaoka Branch School and one of the main characters of the series. She is the younger sister of Suguru, the older sister of Natsumi, and the eldest girl in their small countryside school. Komari is notably short for her age, standing around 140 centimeters according to her own claim though often estimated by others as closer to 130 centimeters, a fact that she is deeply self-conscious about because it causes people to mistake her for a younger child. She longs to be seen as a mature adult and often tries to act older and more composed than she truly is, but her natural personality is far more vulnerable and childlike. Komari is intelligent and generally kind-hearted, but she is also easily flustered, quick to anger when provoked, and highly susceptible to fear, especially regarding supernatural topics. Her younger sister Natsumi frequently exploits her timid nature for pranks and teasing, which often leaves Komari embarrassed or in tears. Despite her frustration with being treated like a child, Komari struggles to project the maturity she desires; she is a poor cook, tends to be clumsy when performing chores, and is often clueless about current trends and romance, though she pretends otherwise. She is also very superstitious, a trait that Natsumi and others sometimes take advantage of for amusement. Within the group of friends that includes Renge Miyauchi, Hotaru Ichijo, and Natsumi, Komari occupies the role of the responsible older figure, even though she is frequently undermined by her own insecurities and by the fact that Hotaru, who is a fifth grader, looks and acts more grown-up than she does. Her relationship with Hotaru is especially significant; Hotaru admires Komari greatly and enjoys spending time with her, and Komari in turn values Hotaru’s company. The dynamic between Komari and Natsumi is central to many of the story’s comedic moments, but beneath the teasing the two sisters care for each other. Throughout the series, Komari experiences gradual personal growth. In the third season, she learns that she does not have to handle everything on her own to be considered an adult and becomes more willing to ask for help. She also improves her cooking skills over time. Her character arc is built around her struggle with self-image and her desire to reconcile her childish traits with her wish to be taken seriously. She has no extraordinary abilities, but her sense of responsibility and her capacity for empathy define her contributions to the group. Her small stature, easily frightened reactions, and occasional tantrums are recurring traits that highlight the gap between her aspirations and her actual demeanor.