Madam Tulpan needed to dominate this guy because he had pissed her off and she had to dominate him. The mistress had to make sure that she left a mark to him and she had to make sure that she used her shit. The mistress then turned him into a human toilet and she made sure that he ate her poo and that he drank her pee. He never forgot what she did to him.
Madam Tulpan had beef with her plumber and she had to ensure that he learned never to take advantage of her. He did a good job but he always took advantage of her ignorance on plumbing issues and he overcharged her on things that sometimes did not need fixing. She had caught him red handed and had to make him pay for it all. The payment was by him eating her shit.
Madam Tulpan was pissed at her slave and she wanted to teach him a lesson. She forced him to endure the kind of pain and humiliation he had never faced before. The mistress turned him into a human toilet and she ensured that he ate it all. When the mistress was done making him do it, she then sat him down and she forced him to do what she wanted.
Madam Tulpan wanted to shock this loser to make him do the things that she wanted him to do and that is why she chose to make him eat her shit. Besides eating her shit, the mistress also got him to endure her trampling using her high heels. She used both pain and humiliation to get what she wanted from the guy and she knew that she had gotten a potent weapon.