Go Ranjou (呉 藍滌) is the current king of Han and has ruled his kingdom for three hundred years. While the kingdom of Han was considered an ordinary middling kingdom, during Ranjou's rule, the kingdom has established itself as a kingdom with very fine artisans and craftsman known for their artwork and high quality tools.
Ranjou is described as an man with an extremely refined and beautiful appearance, such that Youko initially mistakes him for a woman, and proves to be blunt and vocal with his thoughts. Both he and his kirin, Risetsu, are regarded as highly eccentric, much to the bemusement of Youko, Shoryu, and Enki, and they get along extremely well. Ranjou is extremely particular about the aesthetics of everything, rejecting most of the furnishings that Youko offers in the Goldenwave Palace, as well as any servants she attempts to assign to him, except for Shoukei, who becomes frustrated by the king's discerning taste. Ranjou notably does not get along with Shoryu, regarding the king of En as a tasteless and crude man. In contrast, Ranjou appears to have gotten along much better with the king of Tai, Gyousou, commenting that he was unrefined, but not boring.
Ranjou and Hanrin travel to Kei in response to Youko's attempt to help General Risai locate Taiki, though they arrive as anonymous envoys from Han. Though Youko reluctantly agrees to their demand to see Risai immediately, the king of Han brings concrete evidence that Gyousou may likely be alive and presents it directly to Risai to identify. Ranjou subsequently provides Hanrin's services to locate Taiki in Hourai, while frequently clashing with Shoryu during their stay in Kei, and offers the unpleasant conclusion that Taiki's inability to return to the Twelve Kingdoms after so many years may reflect the fact that Taiki is no longer a kirin. After Taiki is brought back to the Twelve Kingdoms, Ranjou and Hanrin return to Han.