"Don't you realize that the longer I deny you the more sadistic it becomes and the more sadistic it becomes the more it turns me on? The longer I deny you the greater the sexual pleasure it brings me. You know what really gets me hot is thinking about getting you to ten years without cumming! That thought makes my pussy gush!"
At this point, with your cock rubbing continuously against Jessica's pussy and having her taunt you in this way, you are getting closer and closer to cumming.
You believe Jessica senses this, because she tells you to stop and she takes a look at your cock.