Guan Xing is Guan Yu's second son and Guan Ping's younger brother. He often works together with Zhang Bao in several instances.

After his father and elder brother's execution, he sought revenge against Wu along with Liu Bei and Zhang Bao. He got his revenge while pursuing Pan Zhang, who had captured Guan Yu and received Blue Dragon as a reward. Guan Yu's ghost appeared in front of Pan Zhang, stunning him allowing Guan Xing to cut him down. When Mi Fang and Fu Shiren returned to Shu seeking mercy, Liu Bei refused and allowed Guan Xing to disembowel them in front of an altar to Guan Yu. Guan Xing and Zhang Bao made a pact of brotherhood.