Mistresses found a new slave who had joined their big family. Since the slave was new to their fold, they had to train him and show him what being a slave meant. Before that, they had to perform an induction ceremony; each slave they had,had to go through that ceremony. They take turns sitting on his face, smothering him. They then made him drink their pee before he was now formally welcomed.
Mistress Qin did not like how unpleasant this guy was. He deserved to be degraded and humiliated and that is exactly what the mistress did to him. He was shocked and he was humiliated as she peed on him and she told him that he had to change if he stood any chance of avoiding such humiliation and torture again in the future. He learned his lesson and he changed.