|Family||Shinnosuke Mizuki (grandfather, deceased)|
|Live Action||Asaka Seto|
Kayoko lived in New York for eight years since she was six, where she became a promising junior diver. She graduated from high school in Japan, and returned to America for six years to study coaching in order to become a diving coach at the MDC. She wants her students to go the Tokyo Olympics and as a result trains her students very hard.
She has long purple hair, as well as purple eyes, She wears a dark purple one-piece swimsuit with pink and blue designs on the sides.