Kyoko is a young woman with oval glasses and a short, black haircut in a Dutch bob style. At the To-Oh entrance ceremony, she wears a black blazer over a white collared shirt. On campus, she is seen wearing a white shirt under a green hooded sweater with a gray hood, and later, an umber, short-sleeved collared dress over a long-sleeved black shirt.
Kyoko enrolls at To-Oh at the same time as Light Yagami and L. When Light and L (under the alias "Hideki Ryuga") are giving their speeches at the entrance ceremony, Kyoko comments that she likes the one on the right, referring to L. Her friend strongly disagrees with her, saying that Light is better-looking.
Kyoko is seen again when Light and L play tennis. When one of the other students returns to the tennis court with news that Light was a former Junior High Tennis Champion, Kyoko points out that "her" Ryuga (L) is holding his own.
Kyoko is last seen when Misa Amane visits Light on campus. She recognizes the star and rushes to meet her, introducing herself as a fan and causing a crowd of people to form around them.