Lady Stefanie wanted to choke this guy because he was a pain in her ass. She did not hesitate to do so because she knew that he deserved to be punished. His luck had run out and it was only prudent for her to punish him and she did not care what he felt as long as her aim was achieved. Needless to say, she achieved what she wanted to.
Lady Stefanie was pissed at her uncle for hitting on her. She felt that it was disrespectful and that he needed to stop that habit. She was not going to tolerate such behavior from him again and that is why she used her leather domination fetish to punish him. He was also ball trampled to add salt to injury and he never tried to hit on his niece again after that.
This guy thought that his lying skills were advanced and that he could do whatever he wanted and get away with it. But lady Stefanie did not feel the same way and she had to punish him for lying to her. That is why she used her trampling fetish to ball trample him and make sure he cried. Before she let him go, she kicked him in the nuts with her heels.