This mistress is hot. And she loves to mind fuck guys in order to get them hooked on her. She knows that when that happens, she has a free hand in dominating them financially. She does not care what happens to them as long as she benefits financially from them. That is the only way they are beneficial and important to her. That is why it is important that her charm does not wear off.
When this mistress caught her slave doing things she did not approve of, she had to show him that there were consequences for it. She was wearing her boots so she spat on them and she made the loser lick them clean. She also made him lick the soles before she felt it was enough punishment for him. He realized that she was not one to mess with and did everything carefully so as not to mess with her.