Madam Tulpan needed to shit on this guy and she felt that the best way to deal with him was to shit on him. That is why she summoned him to the living room and she shit on him. In addition, the mistress also had the guy jerk off as she did it. It was fun for her and she managed to get what she wanted by the time she was done with him.
Madam Tulpan wanted this guy to be more humiliated than he had ever been humiliated before in his entire life. So the mistress did her research and when she was done with it, she knew that using her scat fun was the best way to deal with him. So she filled his face with her shit and had a great time torturing him with it. He had to eat it and lick it as well.
Madam Tulpan did not like how this guy was evading her. He knew what he had done and that was why he tried to evade her. But the mistress wanted to make sure that it did not happen again and so she used her shit to dominate as well as humiliate him. The mistress even went to the extent of making him jerk off while he ate her poop. It worked.