Kou Gyokukan

Lady Gyokukan (玉環の君 Gykokukan no Kimi) was Kou Shouka's great-aunt and a former concubine of Emperor Shi Senka's father.

Appearance
Gyokukan was described as a celebrated beauty in the capital.

Personality & Characteristics
Despite her outwardly elegant appearance, Gyokukan possessed a devious personality and was highly ambitious in regards to advancing the status and power of the Kou Clan. To ensure her goals were met, she would not hesitate to employ ruthless tactics, including executions.

Plot
During her reign as the clan head, she favored Kou Shouka as her successor and engaged him to her daughter Yuri, hoping that Yuri would become the clan head's wife and eventually become the Empress Regnant of Saiunkoku, under the rare circumstances that a woman would take the throne.

As Gyokukan was also aware that princesses of the Shi Clan were traditionally sent to the Hyou Clan to become priestesses, she formulated a plan so that Yuri would not suffer the same fate. To ensure this, Gyokukan forced her daughter to conceal her identity and gender by posing as Yuzuriha, a servant boy for Gyokukan's great-nephew, Kou Reishin, which would also allow Yuri to discreetly learn politics and become familiar with clan affairs. Gyokukan arranged the executions of all the servants who were aware of Yuri's existence, hoping that Shi Senka and the Hyou Clan would not find Yuri.

As her aim to glorify the Kou Clan became increasingly apparent, Senka ordered Shouka, who had already assumed the role of the Black Wolf, to assassinate his great-aunt. Though he greatly admired his great-aunt, Shouka reluctantly complied. When confronting her, Shouka remarks that if Gyokukan were to continue ruling the Kou clan as she had, it would soon fall to ruin. Instead of dying by sword, Gyokukan accepts the cup of tea that Shouka has poisoned and he respects her final request to play the biwa as she drinks to her death.

Skills & Talents
Gyokukan was extremely talented in the Kou clan's traditional instrument, the biwa, and it is said that her daughter's playing style resembles hers. Called the best biwa player of the century, the only person who could rival her biwa was said to be Kou Shouka.