Kuzuha Togashi, three years younger than her brother Yuuta, is a pragmatic first-year middle school student living with him and their youngest sister, Yumeha. Their parents’ frequent absences force her and Yuuta to share household responsibilities, a task she handles with reserved efficiency and practical awareness of family dynamics.

Her childhood exposure to Yuuta’s self-proclaimed "Dark Flame Master" persona during his chūnibyō phase left her deeply embarrassed by his antics. Over time, however, she grew accustomed to his quirks, reflecting a bond tempered by years of coexistence. Though neutral toward Yuuta’s girlfriend, Rikka Takanashi, she unhesitatingly denies any jealousy when their mother probes the topic.

While the original light novel confines her to a brief cameo in its second volume’s finale, the anime adaptation amplifies her role, introducing her in the first episode and weaving her into scenes that emphasize her participation in daily chores and lighthearted family moments. No supplementary media expands her narrative, as available sources solely address her portrayal within the core series.