Li Kouyuu

Li Kouyuu (李 絳攸 Ri Kōyū)  is the former Vice Minister of Civil Administration and Kou Reishin's adoptive son.

Appearance
At the beginning of the series, Kouyuu is a young man, approximately 21-22 years old. He has grey eyes and blue-toned green hair.

Personality & Characteristics
Despite his reputation as a genius, Kouyuu is notorious for having no sense of direction. He's easily annoyed and gets nervous speaking in public. He frequently states that women are nothing but trouble and refused all offers of marriage after he passed the official exam, despite receiving many proposals from politically ambitious families. Despite his short-temper, Kou Shouka describes Kouyuu as a fine young man, mostly due to the influence of Kouyuu's adoptive mother, Yuri.

As an official, Kouyuu is known for being hardworking and loyal and recognizing the efforts of others, as well as a highly capable bureaucrat. However, his dedication to his adoptive father has resulted in Kouyuu ignoring Reishin's shortcomings and completing Reishin's work for him, rather than following his own responsibilities as an official and reporting Reishin's irresponsibility.

Plot
Abandoned as a baby, he was re-orphaned a few years later when his first adopted parents were murdered. As a miserable child slave, he was sold from place to place until finally he was tied to a sacred tree as a sacrifice to the gods, from which Reishin rescued him and took him to Kiyou with Yuri, who was acting as Reishin's personal servant. After Reishin and Princess Yuri married, Kouyuu became their adopted child. In the novel, Kouyuu was originally named 'Kou' by the old couple who adopted him as a baby. Reishin insisted on keeping the original 'Kou' so the name was changed to Li Kouyuu.

At age 16, Kouyuu became the youngest person ever to pass the official examinations, taking the top ranked "Jougen" spot. His reason for taking the Exams and climbing to the top was to stand by Reishin's side and repay his kindness. He also wanted to be acknowledged, having been frustrated by the older man's cool and callous exterior, but eventually realized that Reishin thinks of him as his own child and that the plum blossom, after which Kouyuu is named, is Reishin's favourite.

As the series begins, Kouyuu has been assigned directly to the Emperor Ryuuki, a position that infuriates him because the wandering Emperor never carries out his duties and can rarely be found. After agreeing to be tutored by Kouyuu and assuming a more active role in government, Ryuuki offers Kouyuu an iris flower as a sign of trust. Kouyuu openly accepts the flower as a token of loyalty and his belief in Ryuuki as a worthy Emperor.

The Kou family (specifically Kou Kurou in episode 19) intends to marry Kouyuu to Shuurei to lead the Kou clan in the future. Kouyuu also admires Shouka to the point of being jealous of Ryuuki being tutored by Shouka himself.

In the 13th novel, Kouyuu is imprisoned under accusation of abusing his powers as Vice Minister of Civil Administration department (because Reishin never did any work). He loses this position but remains as an official due to Shuurei's effort.

Ran Shuuei
He has a close relationship with Shuuei Ran, though he loudly denies being the latter's friend. When they were children it is shown that Shuuei often helped Kouyuu find where he needed to go, this continues into their adulthood.

Kou Shuurei
He frequently tutors Shuurei, however, appears to regard her as a friend.