Guan Suo (関索, onyomi: Kan Saku) is Guan Yu's fictional third son and the younger brother of Guan Ping and Guan Xing. He is a famous subject for Beijing opera who wedded four exotic wives. Three Kingdoms fiction may use Guan Suo as their archetype hero for Shu to expand the romanticized lionhearted perception of Guan Yu or the empire.