Mistress Nyx needed this guy to learn his lesson and she knew that it was up to her to do it to him in a way that he would understand and that he would never forget. So she took him to her house and she had fun torturing and degrading him with her strapon suck. He had no choice but to do it as he knew she could make it worse if he did not cooperate.
Mistress Nyx loves to workout and she wanted to workout but she had to punish this guy at the same time. She did not want to sacrifice one for the other and that is why she had to trample the slave and cruelly teach him a lesson. So she stood on his body as she did her workouts and she made him feel pain in the process. And she killed two birds with one stone.