A monk who had intercourse with a xixia princess. He was the 2nd sworn brother together with the 1st, Xiao Feng, and the 3rd, Duan Yu. His martial arts include the 'Tian Shan Zhe Mei Shou' and 'Tian Shan Liu Yang Zhang'. When he first ventured out into the world of Wulin, he had already gained 70 years of inner force (qi) passed on to him by Wu Ya Zi, the leader of the Xiao Yao (carefree) sect. Wu Ya Zi then passed on the leadership of the Xiao Yao sect to Xu Zhu with his entire life's qi. He then died after instructing Xu Zhu to kill Ding Chun Qiu.