Kei Hutchins is Billy and Harold's future daughter in Captain Underpants and the Sensational Saga of Sir Stinks-A-Lot. She has a brother named Owen.
Kei is a young child with shoulder-length black hair and bangs. She wears a dark dress with short sleeves.
- Captain Underpants and the Sensational Saga of Sir Stinks-A-Lot
- She appeared briefly alongside the rest of George and Harold's future families when being introduced to the George and Harold who had traveled there from the past. She was very happy to see her dad once the group returned from their adventure.