Lady Scarlet wanted a favor from this guy and she knew he wanted to nail her. So she agreed to meet him half way. And that for her was to make him cum but not through penetration. Instead, she gave him jerk off instructions and she complemented them with her hot body which she flaunted to aid him to cum. It was as good as penetration for the guy as he had ever experienced it before.
Lady Scarlet wanted to stop being conservative and she felt that the easiest thing to try was to try jerk off fetish. So she practiced on how to tease and when she was confident of her skill, she strip-teased this guy and turned him on like crazy before she got him to jerk off to her instructions. He did all she asked and she felt powerful and sexy at the same time.