Mistress Mystique needed to flaunt her ass and she also needed to shit on this guy. The two things were tied together and she chose to use her hot ass to turn this guy on before she then shit on him. He had no choice but to do what the mistress wanted him to do. He was not allowed to do anything other than what she wanted. So he ate it all.
Mistress Mystique and her friends wanted to humiliate this guy and they did it cruelly by turning the guy into a scat slave. He was made to eat shit from not one but three mistresses. They did it at the same time to make it even worse for him. He had to eat all of them as he was not given a chance to refuse or opt out of the punishment.
Mistress Mystique did not like how negative her boyfriend had become so she had to punish him in order for him to learn to stop what he was doing. He was forced to lick her ass and to endure being choked by the same ass. He was shocked as he did not expect her to do what she had done to him. He realized it was time to change and he did.
Mistress Mystique realized that her neighbor had been eavesdropping on her and she was not happy about it. When she confronted him about it, she thought that he would stop. But she was shocked that he did not and so she caught him doing it again and this time, she did not let him go. She made him eat her shit and drink her urine as punishment and this time he stopped.