Mariko Jinnouchi

She is the eldest daughter of Sakae Jinnouchi and is 71 years old. Mariko Jinnouchi is a full-time housewife. During family gatherings such as Obon and New Year's, she assumes a leading role among the women, coordinating their activities. In emergencies, as the second eldest after Sakae, she often acts as the de facto head of the family. In the story, when Kenji Koiso meets her for the first time, he mistakes her for Sakae. Mariko's avatar is a sun wearing a one-piece dress. Out of all of Sakae's children, she is the only one with no grandchildren.