Goddess Nemesi needed to ballbust this guy and she did so without thinking hard about it. She knew that the guy needed to learn his lesson and she chose to punish him as cruelly as she was able to. The mistress enjoyed how he cried and she made sure he would never piss her off again and with what she did to him, she was sure he was sufficiently scared.
Goddess Nemesis needed to find a way to dominate this guy and she chose to use her ballbusting fetish to do it. She did not care what the guy felt or what he did. All she was interested in was in him doing what she wanted and how she wanted it to be done. He had no choice but to do it as she kicked him in the nuts and made him cry like a baby.