Koku Clan

The Koku Clan (黒家 Kokuke) is the one of the Seven Coloured Clans of Saiunkoku. The clan's name translates to black.

Description
As with the Haku Clan, the Koku clan specializes in military and martial arts. A number of generals in Saiunkoku have come from the Koku and Haku clans.

Koku Yousei
Koku Yousei (黒 燿世 Koku Yōsei) is the Grand General of the Left Urin Army. He is a rival of Haku Raien, the Grand General of the Right Urin Army.

The Black Retainers
Each colored clan has four branch families as their retainers. The retainers of the Black clan are called the Black Retainers or the Black Gates. Only one retainer clan is known so far.

The Son Clan
The Son Clan  was a retainer of the Koku Clan, however the family was purged by the previous emperor. The only known member of this clan is Son Ryouou.