Kaoru Hakumei is a 178 cm tall young man with a well-built physique, shoulder-length dark blonde hair styled in an unkempt mullet, and light brown eyes. His distinctive fashion often features unbuttoned shirts revealing a black undershirt, necklaces like a silver dog tag, and fingerless gloves. UNDEAD stage costumes include fur-lined jackets and peaked caps with chain details. Born November 3rd into a wealthy, influential family acquainted with households like the Himemiyas and Suous, Kaoru experienced a strained and formal family dynamic where personal names were rarely used without honorifics. His mother, a marine biologist who took him to aquariums and the sea during childhood, died before he enrolled at Yumenosaki Academy. Her death contributed to his later search for maternal affection. He carries guilt for leaving older siblings to manage family responsibilities while he pursued personal freedom. During his second year of high school, Kaoru was detached and frequently skipped classes. He managed the livehouse DEADMANS, reflecting a rebellious phase. Initially showing little interest in unit activities, he preferred flirting with girls in town. Despite this frivolous reputation, he possessed natural stage presence and popularity. His personality blends a flirtatious, womanizing exterior with deep-seated emotional vulnerability. Craving validation, particularly from women due to his mother's absence and unsupportive family, he sought relationships offering nurturing affection, though he later vowed to stop "playing with girls." As a core UNDEAD member under Rhythm Link, Kaoru and Rei Sakuma form the unit's "two main leads." Though initially reluctant in group practices, he gradually committed to idol work. His performances mix relaxed, gentle vocals with assertive, glamorous stagecraft. Post-graduation, he continues professionally with UNDEAD, shifting from carefree attitudes to dedicated professionalism, openly stating his motivation is to make fans smile. Relationships reveal his complexity. He frequently flirts with protagonist Anzu, who initially rejects his advances. Their interactions later show mutual care: he rescues her from an aquarium fall and comforts her when overworked, while she supports him during emotional discussions about his mother. He shares a trusted friendship with Kanata Shinkai, bonding over the Marine Bio Club and personal struggles; Kanata provides emotional support, patting Kaoru's head during family crises. Kaoru's dynamic with Rei evolved from mutual annoyance to playful camaraderie, Rei eventually requesting informal address ("Rei-kun"). His initially contentious bond with junior Koga Oogami deepened into mutual reliance, Koga offering his apartment during Kaoru's family conflicts. His hobbies include surfing, reading shoujo manga to understand women, and enjoying desserts like pancakes. He is skilled in housework, including cooking and cleaning, and learned basic guitar from Koga. Despite his playful image, he writes wistful song lyrics reflecting on family and loss. His name meaning—"fragrance" (薫) for his first name and "wing wind" (羽風) for his surname—aligns with his ability to distinguish scents and his carefree persona, symbolized by the seasonal term "kaorukaze" (薫風), a fragrant early summer breeze. Throughout his development, Kaoru transitioned from seeking maternal love to valuing genuine connections. He reconciled with his family's expectations, works earnestly as an idol, supports his peers while acknowledging their growth, balancing a lighthearted facade with confronting deeper emotional wounds.