I guess even today, I feel a bit uncomfortable if someone I know is seeing me naked (to avoid that I always attend to gyms or Public Pools away from my neighbourhood)
I had this experience some years ago:
My Mom and Aunt (her Sister) worked as Nurses at a Public Hospital. On one occasion the Staff of the area they were working in (Men and Women) organized a short Trip to spend the day in a Country Club located 190 miles away from the City into the country side. Everyone along with their families.
My Mom didn't want to attend but my Aunt did with her daughter (my cousin) and her Husband
They invited me to join them and it was an invitation I wouldn't pass (besides I knew almost all of the Co Workers well since I was a kid, when my Mom started working there and they knew me as well) so I was sure we'd spend a great day together.
When we arrived there we realized it was a really nice place. Among the Country Club facilities there were Soccer Field, Tennis, Volleyball Courts etc,etc, there was that big semi Olympic Pool. what we enjoyed the most. It was perfect! We spent almost the whole day in there (although the spring weather was only mildly hot)
In order to make it to that Country Club, the Staff had rented a Bus with its Driver (a Guy in his 50s) to take us to and back from the country club, so he was also able to enjoy the Club's installations.
By 6 pm he let the people know we should be leaving at 7 pm, so every one go to change clothes and prepared their bags and belongings to get in the Bus. I remained in the pool about another half an hour, but then I Rushed to the Men's Locker Rooms to Shower and wash off the Chlorine from my body and swimming trunks.
When I got inside I was the only one in there.
Everyone else had already changed and left. I carried my Bag, put my dry clothes on the Bench, stripped naked taking my bathing suit off, and started to shower. The afternoon had got pretty windy, I started chilling a bit with my wet body when I exited the Pool, and to top it all, the shower water was extremely cold. I was the only one there, so I decided to wait under the shower stream for the water to heat or at least get a bit warm (it never happened)
The pretty small locker room area had a row on 6 single shower heads with dividers but no Curtains by a wall, and the Benches in the opposite wall. So there I was, alone, totally naked, kinda shivering while soaping up my Body and waiting for the Hot Relaxing water to come and warm me up.
I lost the sense of time, I didn't realize it was getting late and by then all of the people were already on the Bus except for myself.
My Aunt kinda worried wondering why I was taking too long. So one of her (and my Mom's) Co Worker offered himself to go to the Locker Room to check for me.
His Name was Albert and he was a man (probably in his late 50s then) that I knew since I was about 8 or 9 years old (I was 23 when this incident happened) Apparently once in the locker he called my name but I didn't hear him because of the water running, so he peeked in the Shower Area and approached next to me to tell me I had to finish and hurry because I was the only person left from all on the Bus.
He caught me by surprise when he spoke to me, I was distracted cursing because the water never got warm.
Of couse although he knew me since I was a kid, he had never ever seen me Naked before, prior to this day. . He looked me from head to toes with really wide open eyes. He probably got surprised too by the size of my Goodies. Because of the cold water, my Willy had shrunk to about 2,5 inches (I'm uncut) and barely peeked from my full bush. On the other hand, my Hairy B*lls got tight as a Nutshell, so I wasn't in the best shape to be seen displayed naked.before him.
Fortunately he remained there for only about 2 minutes and left, telling me again to hurry up
It was the one and only time he got to see me naked (so he never knew I could have had a better "state" or a more appropriate size, if the water would have been Warm enough)
By that moment I didn't feel that embarrassed but it certainly was an Awkward Situation, because it was a person that I had known for so long.