This is a true story from years back but I always will have great memories of it.
I had been traveling across country and had been driving for many hours and was getting bleary from it. So I decided to get off the interstate and find a place to sleep for a few hours, maybe get some breakfast and then continue. I pulled off onto a state road and came upon a small town. Just as I got into town there was a small park so I thought this would be a great place to shut down for a couple of hours and since it was past midnight I was sure I wouldn't get a room so I pulled in and got ready to kick back and sleep. I had to take a bathroom break so I wandered over to the toilets. No one was anywhere at this hour in this little berg so I took a seat and relieved myself. I noticed a penciled message next to the dispenser that said simply "Have fun" and contained a phone number and a time. It had only been there for 30 minutes and I thought what the heck so I erased it and went to find a phone (pre-cell days!)
A man answered the phone and I told him I had got his message. He laughed and told me he was in the cabin 6 up the road a bit if I wanted to come by. I did and quietly knocked on the door of this place with several little cabins surrounding a parking area. Looked like it was something out of the 30's.
He answered the door and invited me in while looking me over. He was about 45 and around 5'9 with a bit of a paunch but a decent looking man. I came in and sat on the edge of the bed and he offered me a drink. He told me he was an OTR trucker and was having to take a mid-week break because of his log book being full for the week. So he was here for three days and had been bored so he put that ad up that evening.
Now I was mostly straight but had had a few fun times with school mates playing with each others dicks and such but was more into women. However, he seemed decent and I was really horny from all the driving so I asked him what kinda fun he mentioned in the ad. With that he pulled down the sweatpants he was wearing and said "This kind of fun!" His semi-hard cock was now on display. He wasn't particularly long but very thick and had one of those dicks shaped like a wedge. Smaller prominent head and really wide in the middle. The head was a dark purple and his cock was veined and he had low hanging balls. I smiled and said that will do just fine and he came over to where I was sitting and dropped his sweats to the floor.