Kai Liu is the illegitimate daughter of King Richard Stirling and Karen Liu.

Forbidden by King Aldous to marry, her parents conceived her when they were sixteen and eighteen years old, respectively. Kai has spent her childhood thus far living at Castle Vallon, where she is well cared for by her parents, but must live with the stigma of illegitimacy.

Since Richard became king, Karen has been pressuring him to marry her and legitimize Kai as his daughter and heir. However, the Council opposes this action, primarily because most of them have plans of their own for Richard.

One of the councilors, Joan Dychauk, has sought to betroth her son Baldwin to Kai if she were to be legitimized. If she is not legitimized, the widow Joan intends to marry Richard herself.