Hagumi Kitazawa is a third-year student at Hanasakigawa Girls' High School and the bassist for Hello, Happy World!. Her family runs Kitazawa Meats, a butcher shop famous for its croquettes, where Hagumi often helps out. At home, her parents frequently clash, with her mother prone to emotional outbursts and her father vanishing for days after arguments. They disapprove of her energetic, tomboyish nature, believing it inappropriate for a girl, pushing her towards sports as an outlet. Physically, Hagumi has bright orange hair and copper eyes. Standing at 152 cm, she is the shortest member of Hello, Happy World!. Her casual style mixes sporty and feminine elements, like sundresses with jackets, or seasonal wear such as knitted sweaters in winter and college jackets in summer. She often accessorizes with animal-eared beanies. Her personality radiates boundless energy and cheerfulness. She loves athletics, serving as captain and ace of the local softball team, Sky Stars, and excelling in marathons. Despite her athletic skill, she feels insecure about her boyish appearance and adores cute things, especially Michelle's bear costume. Highly sensitive to others' emotions, she avoids competition, believing losers inevitably feel discouraged. This empathy fuels her dedication to Hello, Happy World!'s mission of spreading happiness. Hagumi speaks in the third person and uses affectionate nicknames like "Kokoron" for Kokoro Tsurumaki and "Mii-kun" for Misaki Okusawa. Her musical journey started when her older brother taught her basic guitar, easing her transition to bass. She joined Hello, Happy World! to promote joy through music, aligning with her aversion to sadness. Academically challenged, she shines in physical activities, demonstrating exceptional speed, flexibility, and skills like performing backflips—even in costumes. She is also proficient in karuta. Notable relationships include her childhood friendship with Kasumi Toyama, though she initially didn't recognize Kasumi after a hairstyle change from cat ears to twin tails. Hagumi shares a bond with Saaya Yamabuki, expressing interest in collaborating their family businesses—her meat shop with Saaya's bakery. She seeks fashion advice from Himari Uehara and Chisato Shirasagi to blend her sporty style with feminine touches. Hagumi treasures a monkey stuffed animal named "Monkey," a childhood companion her mother repeatedly mends. It symbolizes comfort during solitude amid family tensions. Her character design in crossovers, like the Ojamajo Doremi collaboration, drew inspiration from Fujiwara Hazuki.