The Sa'kagé were the criminal underworld of various cities across Midcyru, the most powerful and evident one located in Cenaria. This strength was the main reason that Khalidor didn't invade Cenaria straight away.
In Cenaria, they controlled all of the crime in the city, including the prostitution, smuggling, assassinations, the guilds, etc. They employed a large number of wetboys and owned all the brothels in the city. They controlled numerous safehouses for their members and bribed and employed a number of powerful individuals, such as wetboy Durzo Blint.
The Shinga was the head of the Sa'kagé. Momma K was the Cenarian Shinga for over fifteen years, hiding behind various puppet Shingas to keep her identity a secret, such as Pon Dradin. She gave up her title to Jarl, who declared himself Shinga and was supported by Momma K. Consequently, many of those who knew the identity of the real Shinga thought Jarl was only another puppet. After Jarl's assassination, Momma K assumed the role of Shinga again.
The council to the Cenarian Shinga consisted of nine of the most important Sa'kagé members. The Nine and the wetboys were the only people who knew the true Shinga's identity. They were all given titles relating to the area of the Sa'kages trade which they held sway over, though not all were brought to light. The only two titles revealed were the Master of Coin (master banker and accountant for the Sa'kage), and the Mistress of Pleasures (manager and owner of all brothels - also functioned as a spymaster using intelligence gathered by prostitutes from clients with loose tongues). Count Drake and Pon Dradin are the only known holders of the title Master of Coin. Momma K was the only known Mistress of Pleasures. Jarl was Master of Pleasures and Shinga for a short period until he was assassinated by Vi Sovari .
Kage means, "Shadow," and Sa'kage means "Lord of Shadow." Blint alludes to the Sa'kage has a connection to the Night Angels.
Kage is the Japanese word for "shadow" and is pronounced the same as it is in the story.