When this mistress realized that this guy did not fear her, she knew it would not be easy working with him as she wanted someone who feared her so that he would not want to disappoint her. That is why she used her trampling fetish to crush and stomp on him. After what she did to him, he got scared of her and that is how he never did anything to piss her off.
This mistress is plus size and she loves her body. She even has guys who love her big body and have a fetish for it. So he thought that by calling her fat, he would make her want to shed weight and she would be distraught. But she was not and instead of that she punished him cruelly. The mistress did this by trampling him as cruelly as she could.