- "Yeah, I can make deliveries!"
Mizue Ookawa (大川 瑞恵 Ōkawa Mizue) is the oldest daughter of Tomio Ookawa and Kazuko Ookawa and their second child. She is the younger sister of Atsushi Ookawa and the older sister of Yutaka Ookawa.
- The name Mizue means "felicitous omen, auspicious" (瑞) (mizu) and "favor, benefit" (恵) (e).
- Mizue's surname Ookawa means "big, great" (大) (o) and "river, stream" (川) (kawa).