This mistress wanted to dominate this loser and facesit him to pass time. That is exactly what she did and she had a great time doing it. It was a lot of fun for her but it was torture for the loser as he had to endure all that she did to him. He had to endure the pain of being facesat on as well as that of being choked.
This mistress does not like ineffective people. She had to teach the guy to do what she wanted and how she wanted it. So she took it upon herself to teach him how she wanted him to behave. And that is why she facesat on him so as to teach him a lesson and have him change his attitude so that he would be effective. He had to be to avoid such humiliation.