Rikou (利広, Rikō) is a cheerful and perceptive man from Sou, revealed to be the second son of king of Sou, Senshin, and his wife, Meiki. Unlike his brother, Ritatsu, and his sister, Bunki, who serves as the Chief Physician of the National Hospital of Sou, Rikou does not aid his father directly with the administration of the government. Instead, he frequently travels around the Twelve Kingdoms, sporadically returning to Sou to provide news of what is occuring in other kingdoms to his father.
In The Aspired Wings, Rikou encounters Shushou in Kyou as she heads towards the Yellow Sea in order to ascend Mount Hou. Though he learns that she intends to ascend Mount Hou to become the next king of Kyou, he does not attempt to dissuade her after seeing her confidence, despite her age. After he aids Shushou by obtaining an official document that will allow her to travel with her moukyoku, Hakuto, without causing suspicion as to who she is, they part ways.
However, when Shushou enters the Yellow Sea after hiring Gankyuu, a youjyuu hunter, as her guard, Rikou is there, apparently wanting to help protect her as she ascends the mountain in spite of his lack of experience in the area.
In addition to his appearance in The Aspired Wings, Rikou also appears in the short story Kizan, investigating the status of the kingdom of Ryuu after the events of The Twelve Kingdoms: Skies of Dawn. In Ryuu, he encounters his recurring acquaintance, Fuukan; despite having run into him a number of times over their long lifetimes, Rikou knows little about Fuukan, except that he hails from En and that he is likely someone high up in En's government structure. Having lived for six hundred years, Rikou reveals a keen eye in noticing when a kingdom will fall and notes the unusual nature of how Ryuu is tilting towards ruin after one hundred and twenty years.