Mistress Iside wanted to shit on her business partner because she felt that he did not do what they had agreed on and she also felt that he was secretly sabotaging the business. That is why she chose to dominate as well humiliate him with her shit. The mistress chose to make the guy eat her shit and she did not care what he felt. He had to do what she wanted.
Mistress Iside realized that this salesman was trying to dupe her and she did not like it. She had to make him learn his lesson and learn it the hard way. That is why she chose to torture him with her shit. She did not want anyone else to have to go through what she went through. That is why she had to make it as cruel as she made it.
Mistress Iside had asked her slave to do some chores for her but he refused and she could not believe the nerve he had. As she resorted to punish him, she felt that the best way to deal with him and with the situation was to make him eat her shit. The mistress also recorded it and kept it in case he forgot and messed up again. Luckily, he never messed up again.
Mistress Iside had given these guys some work to do for them but they misbehaved and did not do it as well as they wanted it to be done. The mistress was so pissed at them that she had to teach them a lesson. That is why she went out of her way to shit on them and to make them eat her poo. They never repeated their mistake as they knew what would happen.
This guy was too stubborn for mistress Iside and she felt that it was up to her to do something to him. The mistress used her shit to deal with him and by the time she was done with him, she had no doubt in her mind that he would never be stubborn again. He not only ate her shit, but he also drank her pee and it was the most degrading thing he had ever done.