When I was in college, I went to go visit a friend during spring break. I needed to take a shuttle van from the airport to his house. It was a couple hours out of the city. The shuttle had 5 rows and 3 large rectangular windows on each side for the passengers. When I got picked up at my terminal, there was the driver and one young guy passenger who was seated in the 1st row behind the driver. I was happy it was mostly empty and sat in the last row on the left. I was surprised no one else got on as we left the airport. Time for a nap. I woke up some time later, and everything looked the same; the driver was driving, and the other guy could have been awake or sleeping. The only difference was that I was hard. I’m wearing a gray tshirt and blue athletic Nike shorts, and I’m looking down at my tented shorts. I can’t help but grab my tented dick at the end, squeeze, and push down. Like a natural reaction. My fingers are rubbing the bottom of my shaft from outside my shorts, moving up and down, up and down. These shorts are mid thigh, so I release my dick and just start massaging my right thigh…on top, then outside, top again, then inside. I stick my thumb up my shorts, push under my jockstrap, and graze my balls. I sigh. Being in the back, no one can see anything, and we’re on a 2 lane highway with not a lot of cars, and I’m higher anyway than the sedans. I keep squeezing my inner thigh and rubbing my thumb on my balls. After a couple minutes, I grab my dick again from the outside and push down and release, multiple times. I realize I can’t stop and my dick won’t go down. I lift my shirt a little and push my hand under my shorts but over my jockstrap. I grab my dick and squeeze, feeling the fabric against my dick. I release and finally pull my hand out but now go under my jockstrap. I curl my fingers at the base of my shaft and as I move toward the head, I feel it’s wet with precum. I had to tell myself to exhale as my index finger went over the head, smearing my precum while simultaneously giving one stroke up. I was content stroking my dick like this for a minute when all of a sudden I wanted to see my dick and see me stroking it. So with my left hand which was doing nothing at this point, I pulled on both waistbands over my right hand and held it underneath my balls. It felt great for my dick to be exposed to the air. I’m watching myself slowly pulling on my dick for a little bit when all of a sudden I see out the window an ambulance right next to the shuttle. I immediately release my dick and cover myself. I look and it’s just driving normal and it’s two guys. I can clearly see them and the passenger can see me because he is looking at me directly and starts to motion his hand like jacking off in the air. Oh shit! I was so absorbed in my jacking off I did not see them. I was instantly panicking and looked away from the window. But I can see it’s still there and when I look again, he is doing the JO motion but then a thumbs up. Oh. Oh! The ambulance was the right height to see inside and he was looking at me. He looked cute with his dark hair and sunglasses. He motioned again. And thinking he wanted me to continue, I pulled my dick out and he gave me a thumbs up. I kept on stroking, watching him watching me. This was just too hot, and after taking a glance in my shuttle that everything was still the same, I looked back at him. My left hand pushes my shorts down and I lift my shirt about half way, and as I’m staring into those sunglasses I start to cum on my stomach. After a few shots, I feel my cum oozing out onto my dick head and fingers. I see him smile and he gives a thumbs up and then they drive past the shuttle. The part with the ambulance was not even a minute; I was so horned up. I finally clean myself up and settle in for the rest of the ride.