The courtier is a young man who is imprisoned because he engaged in an affair with the king's daughter, the princess.
The king is a man who enjoys giving prisoners a choice as to their fate. He has developed a system that has the prisoner choose between two doors-one leads to freedom, the other to an arena and certain death. He takes vicious strides in choosing the tiger for the young man who engaged in an affair with his daughter. The other door has a lovely woman who he must wed should he choose that door.
The lady is the young woman who is behind the other door. She causes the princess much jealousy and anguish.
The princess is in love with the young man. Her red-hot jealousy is causing her to consider letting him go to the arena and be ripped apart by the tiger, rather than living with his marriage to another woman. The choice is never revealed to the reader.