This mistress is a control freak. She loves to control people and to be in charge and that is what happened today. She had to make sure that everything worked out the way she wanted it to. That is why she had to be as humiliating and as cruel as she could be so that the slave would not think of disobeying her or trying to mess about with her.
This mistress was out to tame this guy and she did it with her sph fetish. She did not want him to think that she was scared of him or that he would be allowed to do whatever it is that he wanted. Instead, the mistress chose to cruelly torture him and she did it with her sph fetish. She had him do a lot of humiliating things to himself as she watched and enjoyed.