This is a true story.
When I was around 16 I travelled to Mexico with my then girlfriend's family. We went all the way from Florida to San Juan de Los Lagos, so the drive was VERY long. We were in an SUV, I can't really remember the model/make but it was white and it was myself, girlfriend, her brother, mom, dad, a cousin and Aunt.
My girlfriend and I rode right in the back (no seat), the vehicle only had two rows of seats. With the high back on the second row, the other passengers could not see what was going on in the back.
We spent hours touching and feeling each other during the long road trip. The best part was when we were driving at night, her brother had got in the back with us.
My girlfriend laid her head on my lap and stretched out in the foetal position. It was dark so she started rubbing on my cock which was rock hard in no time. She finally pulled the head out of the bottom of my shorts and started jacking me and rubbing the head with her thumb! Her brother couldn't see because it was too dark so it was really hot getting jacked with her whole family in the car.
I bent down and whispered that when I was ready to cum I would tap her on the shoulder. She managed to find a cloth near us as it didn't take long and I shot a huge load into it.
The best part was that her brother was talking to me at the exact moment I shot into the cloth, and he had no clue! He couldn't see because it was so dark. I still get hard thinking about that episode in my life. It was so HOT!