TV-Series
Description
Kayo Zenna is a minor character in the anime Hyouka, introduced as a young relative of Mayaka Ibara and the younger sister of Rie Zenna. She is approximately ten years old and in the fourth grade, placing her in elementary school during the events of the series.

In terms of her physical appearance, Kayo is depicted as a girl with shoulder-length brown hair which she typically wears in two low braids. Her bangs hang on the right side of her face, and she possesses light brown eyes. Her demeanor stands in contrast to that of her older sister. While Rie Zenna is more assertive and known for labeling her possessions, Kayo is characterized as being quieter and noticeably shyer.

Kayo’s primary role in the story unfolds during a single episode arc where the main characters investigate a perceived mystery involving a ghostly figure seen wearing a kimono in a storehouse. It is revealed that the apparition was actually Kayo herself. She had borrowed a kimono belonging to her older sister, Rie, without seeking permission, fully aware that Rie would not approve of her using it. This act of borrowing the kimono leads to the mistaken sighting that the protagonists, particularly Eru Chitanda, initially find puzzling. Her actions serve as the catalyst for a minor mystery that allows the main characters to explore themes of familial relationships and unspoken feelings.

Her key relationships are defined by her family ties. She is the younger sibling of Rie Zenna, and their dynamic involves a typical sibling contrast in personality and behavior, where Rie writes her name on her belongings to mark ownership while Kayo does not. She is also a relative of Mayaka Ibara, whom she affectionately refers to as Maya-chan. As a character who appears only briefly, Kayo Zenna does not undergo significant personal development within the narrative. Her notable characteristics at the time of her appearance are her shy personality and her role in the borrowing of the kimono, an act which drives a small but key plot point in the series. Her motivations in that moment are simple and relate to a child's desire to wear a beautiful garment, even if it means going behind a sibling's back.