This guy ruined lady Scarlet's day and she was not going to let him get away with it. She had to make sure that he also had his day ruined. She chose to do it herself and she did it with her facesitting fetish. He cried and begged her to stop but she ignored him and went on doing what she wanted to him as she did not care what he felt. She wanted him to get the message.
This girl had borrowed money from lady Scarlet but she was having issues repaying. The mistress got pissed and fed up with her excuses and she had to act in order to get her money back. That is why she used her facesitting fetish to dominate and humiliate her. The mistress facesat her and choked her with her ass so as to send a message to her. It never happened again.
Lady Scarlet knew that she did not want to fuck her boyfriend. She was not in the mood for sex. But she also knew that if she told him that, he would be crushed and that it could affect him. So she did what she knew was guaranteed to get her the same results. She facesat on him knowing he did not like it and he would be turned off. And it worked.