Mistress Mystique was disappointed in this guy and she knew it was good for her to punish him so that he learned never to mess with her and to stop being dishonest. So the mistress used her hot ass and made him worship it. In doing so, he had to lick it and smell her farts as well. She nearly choked him as she did her thing on his face.
Mistress Mystique was dying to have her ass worshipped so she made this slave do it. It was easy for her to do that as she made it look like she was doing it as a punishment to him. He was shocked but what she asked him to do but he knew that he did not have a choice but to do what she had asked him. It was more of an order.