Cho-Tzu is the main settlement on the Shenchu Bay island in The Shackles. It is built around a large triangular harbor.

Most of the harbor is used by the Shenchu pirate vessels and the merchants ships. A second city is formed in the remaining part of the harbor consisting of 50 or more junks, rafts, and other ramshackle watercraft occupied by over 200 Tian-Sings, descended from sailors from Unknown, the floating city of Minata. These folk rarely set foot on dry land and are known to provide services from fortune-telling to midwifery but can also be hired as thugs. Most of the inhabitants of Cho-Tzu are Tian-Sings but the ramshackle neighborhoods on the northernmost side of the city are populated by Tengus who escaped from Imperial Lung Wa long ago.