Who is Xie Rong from Death of a Red Heroine and what is their importance?

Xie Rong is the tour guide on Guan and Wu's visit to the Yellow Mountains. She is independent, feisty, and curious. She witnesses Wu taking obscene photos of Guan. Wu seduces her. She has no objection to his advances since she knows Wu and Guan are unmarried. Guan finds out and confronts Xie, calling her a whore. Wu has to pull them apart and he abandons Xie. Shortly after this trip, Xie quits her position at the travel agency, though she denies it was because of the incident with Guan.