Who is Uncle Lu from Snow Flower and the Secret Fan and what is their importance?

A Jinshi scholar, Uncle Lu's connections with the government are the primary reason for the Lu family's wealth and status. When Uncle Lu loses his position with the change of government when the Chinese Emperor dies, he is forced to come home to the Lu home in Tongkou. He chooses Lily's first son as a pupil, and tutors him; her son eventually goes on to be a great scholar like Uncle Lu. Uncle Lu has moles on his face with long hairs protruding from them, with which he proudly plays.