- Birth Name: Gu Yun (古筠)
- Stage Name: Xiao Yun (小筠) (Taiwanese), Guu-chan (グーチャン) (Japanese)
- Birthday: December 14, 1996
- Blood type: O
- Hello! Project groups:
- Ice Creamusume (2008–2009)
Before participating in the Hello! Project Taiwan audition, Guu-chan was part of a dance troupe that performed regularly and still is a part of it, though due to her activities with Ice Creamusume she doesn't participate in all of their performances any more. She was one of the four finalists chosen to become Ice Creamusume. Her father is a famous athlete.
Due to being busy with school and her dedication to achieving good grades, she doesn't blog very often and isn't always able to participate in Ice Creamusume activities. In 2009, she graduated from elementary school 10th of her school.