A member of the G.S.O. rounder team, he is Changpo's colleague (and unofficial younger brother). He is actually an android created by a government organization research group, and was rescued by Sakurako from the harsh frontier after a certain incident. He currently works at G.S.O. under Sakurako in something resembling a parent-child relationship.
His puppy-dog-like appearance prompts Changpo to treat him like a toy, and he has become the facto mascot for Sakurako's team.
Sakurako made sure to register Cuilan as 15 - the legal age of adulthood - so that he would be considered old enough to work at G.S.O.