Too good to pass up

My aunt Ronnie (Veronica) 48 like to party and drink heavily, married to Arnold 54 very rich and a no nonsense type. Their two children were at college, I 23 worked locally as a mechanic and also done car repairs in my spare time. Which I'd plenty of, no girlfriend nor a great dating record. My life was my paid work and doing car repairs in my spare time for extra cash. By car repairs I mean everything bodywork to engines, so when Ronnie drove off the road when drunk she panicked because Arnold would take away her car and stop her partying. Arnold was away for three more days; she wanted me to fix her dented fender asap. Not hard install a new fender after painting it to match the car. But I would have pay for the fender the paint up front and Ronnie pay me back slowly as Arnold kept a close eye on her spending. I could afford it, but what was in it for me, So, I reluctant Ronnie was really desperate. She knew of my failed social life, so offered me sex to fix her car before Arnold found out about it. I agreed insisted on a fuck up front, then got to work on the car. Arnold didn't waste money on expensive cars; Ronnie was sensible car nothing flash. Also, its model was almost the same as the previous model only a new engine, new grill and different taillights mostly, other minor changes but the fenders were the same. I was able to get a secondhand fender same color as her car and fit it. A quick cut and polish it was as good as knew. Which was lucky as Arnold returned earlier than he thought he would. Ronnie was happy I'd saved her ass as she put it, I said just as long as get to use it with a large grin on my face. She kept her word, and I get to fuck whenever Arnold is away. A bonus is that Ronnie likes sex, parties when Arnold is away because she used to get no sex. Till now, providing me sex has reduced her partying quite a bit. She has also paid me back for the fender, the sex is now for our mutual benefit.