My son and I were coming back from an out of town tip the other night. We picked up a hitchhiker, a cute teen whore named Hillary. She knew how to get a ride. She was in a short skirt and high heels. She was lacking underwear, so when the wind blew, she showed off her ass and pussy. She may have not wanted a ride from a woman, but my son was in the car. We had the car packed, however, from our trip. I was all ready to move some stuff around, when she said, “I can just sit on his lap,” pointing to my son. My boy had a huge grin and an even bigger boner. Hillary sat her hot teen slut ass on his lap. My son put the seat belt around them both. She gyrated on his lap. He was moaning. It was distracting as I drove. Hillary slide her hand back to unzip his pants. A little adjustment and his cock was in her cunt. She braced her arms on the roof of the car and bounced on his cock until he came. I had to rub my pussy. It was so hot watching a cute hitchhiker fuck my son on I-95. As I started to reach my hand into my pussy, Hillary stopped me. She purred at me, licked her lips, and said, “Safety first. Let me help.” That cute little teen masturbated my pussy until I came on her fingers. Then, she fed those fingers to my son. When we dropped her at her destination, she kissed my son, winked at me, thanked us for the lift and said, “ass or grass, nobody rides for free.”