Goddess Kira knew that this guy could get turned on by what she did. She was out to dominate him and she wanted to do this with her sexy ass as well as with her female domination. That is what she did by teasing him and then humiliating him a little. He was confused as he did not understand what she was doing or what she was planning to do to him. But he was turned on as it was something new to him.
Goddess Kira wanted to dominate this guy in order to scare the shit out of him. That is why she went out of her way to humiliate this guy and do things that he had never done before. The mistress used her hot body to tease him and when she had him where she wanted, she teased and denied him before she turned cruel and scared him like he had never experienced.
Goddess Kira felt that this guy was being inconsistent and she did not like it. She felt that the best thing to do in the circumstances was to torture him and she felt that she had to do it in a way it had never been done before. The mistress made him humiliate himself and this was done by having him jerk off to her cruel instructions while she recorded him.