Oosawa Mizue

Oosawa Mizue is a minor character in the Phantom Bullet Arc and the daughter of Oosawa Sachie.

Appearance
Mizue has brown eyes and dark hair tied in two braided pigtails. She wears a kindergarten uniform consisting of a white blouse, a dark blue skirt, and a red bow pinned at the collar, and carries a yellow pochette slung over her shoulder.

Phantom Bullet Arc
On December 16, 2025, Mizue accompanied her mother to the Dicey Cafe after Sachie was contacted by Kirigaya Kazuto, Shinozaki Rika, and Yuuki Asuna the previous day. Waiting in a private room at the back of the cafe, Mizue and Sachie entered the main room once Asada Shino was informed of the situation. As Sachie explained to the confused adolescent how she had been pregnant with Mizue the day a man attempted to rob the post office where she used to work five years prior, the little girl followed her mother in repeatedly bowing to Shino. After Kazuto declared to Shino that she had the right to consider the lives of those she saved, Mizue withdrew from her bag a handmade crayon drawing of herself with her parents addressed to Shino as her older sister. Giving the drawing to Shino, the child carefully recited her thanks to the older girl for saving her and her mother. When Shino began crying, Mizue gently reached for and held her hands.