Nanase Togashi is the mother of Yuuta, Kuzuha, and Yumeha Togashi. With her husband working overseas, she serves as the primary caretaker, managing the household and handling day-to-day family responsibilities.

Portrayed as warm, kind, and nurturing, Nanase consistently supports her children. She demonstrates understanding regarding Yuuta's past struggles with "chūnibyō" and his "Dark Flame Master" persona. Aware of his embarrassment, she avoids pressuring him to conform and accepts this phase as part of his growth. She shares a close bond with daughter Kuzuha, frequently engaging in shared activities like cooking or assisting with homework.

Her approach reflects awareness of her children's emotional needs. She allows them space to navigate challenges while providing a stable home environment. This is exemplified when she encouraged Yuuta to accompany Kuzuha on an errand, indirectly facilitating a moment where his past chūnibyō behavior resurfaced, though she did not intervene directly.

Her character remains consistent across the series, films, and other media, with no significant development depicted. Her background is unchanging: a middle-aged woman dedicated to her family's well-being, offering emotional support and maintaining household stability amid her husband's absence. She appears in light novel and anime adaptations, with minimal involvement in major plot events.