(深見 小夜子 Fukami Sayoko): Sayoko (Nicknamed "Sayo") is a supporting character, who appears in the third mystery involving the puppet workshop. She is a young girl, whose best friend is a black cat named Ririsu. She takes a liking to Sakon and Ukon, and calls them her friends; even going as far as calling referring to Sakon as her brother. Eventually, her cat Ririsu disappears, causing her much sadness.
Sayo makes a small appearance in the last episode, she appears entering the theater, to watch Sakon's play.
Sayo is very kind, and happy go lucky.