Seitaku (鴨世卓, Ou Seitaku) is the current monarch of the kingdom of Ren, who appears in the novels when Taiki is sent on a diplomatic mission to Ren in order to thank Renrin for lending her assistance in returning him to the Twelve Kingdoms the first time. His relaxed personality is reflected in his first ordinance as king: he requested only that his people be happy.
An easy-going person, Seitaku comes from a farming family and spends most of his free time growing crops in a private garden in the Inner Palace. His farming background means that he is unfamiliar with politics and often requires Renrin to help him sort out issues. Though Renrin often chastises Seitaku for not being formal enough, they both get along very well. Seitaku's easy-going personality also allows him to get along with Taiki very well and he takes a liking to the young kirin, treating him as an ordinary boy rather than someone who must be revered.