Lady Scarlet does not like dealing with selfish people. When she realized that this guy was selfish, she had to dominate him and she had to do it in a way that the guy would not forget. The mistress chose to use her shit to degrade him and by the time she was done with him, he had realized that he had to change so as to avoid such degradation.
Lady Scarlet had a debtor and she wanted to humiliate the guy in a way he had never done before. She had tried to get her money from him but he did not want to give it back to her and so she had no choice but to punish him in any means necessary so that he paid her back. The mistress cruelly used her shit to pass the message and to humiliate him.
Lady Scarlet had never imagined that there was something like scat fun. But when she came across it, she knew she had to try it. She was actually bored and had enough time on her hands to try it. She also had a slave who had pissed her off so she had all she needed to try scat fun. So she dived in and she enjoyed how degrading it was for him even though she was uncomfortable with it at first.
This guy had both fun and humiliation from lady Scarlet. She teased him and she had fun with him as he licked her pussy and her ass when she facesat on him. But then again, and without any provocation whatsoever, she took a dump on his face and into his mouth. He was shocked and he learned that she was into scat fetish. He could not do anything other than beg her to stop.
Lady Scarlet had a nosy and noisy neighbor and she dominated him for it. She knew no punishment would work him other than using her shit. So she did not bother trying anything else. She went directly to scat fetish and she used it to punish him. He was tricked to go to her house and he thought he would get to have fun with her but it ended up being a cruel and degrading punishment.