I'm a 30 something man giving my wife, Elizabeth, a backrub in our bed. She's a pretty, petite blonde woman with meidum sized breasts and the toned body of a former dancer. As I start to give her a back rub as she lies face down on the bed, I secretly swap out the massage oil without telling her. The new oil has a secret pheromone formula that causes any woman it touches to become desperately aroused. She gets more and more turned on as the backrub proceeds, and begins to try and seduce me into sex. I keep turning her down and continuing the backrub which makes her more frustrated and her attempts at seduction cruder and more overt, until finally she's begging me to fuck her and using intense levels of dirty talk to entice me. Still I refuse, and now she feels like she's losing her mind. Finally, I relent by taking the tip of my pinky finger and gently running it over her pussy lips and clit one, single time. This is enough to send her into an orgasmic explosion and she gushes all over the bed, convulsing and babbling senselessly. She looks up at me afterwards in awe and feeling a new sense of submission. Tell in great detail with lots of dilaogue and physical description. Tell in present tense.