My older sister watched a couple of times. I had a close friend who watched me get one during a sleepover.
I received several at the doctor's office, with other boys present, but they were getting enema too, so i saw them also.
When I was 13 and 14, my mom commonly gave enemas to children in the neighborhood and town. I was always used as the example for them. My mom would tell me I had to stay home that morning and she would tell me how many boys or girls were coming that day
I would end up on the bathroom floor on my back with my hairless anus accepting the nozzle and my erect penis, testicles and pubic bush in full view The girls were especially interested in my erection and pubic area. I would expel and return to help mom. This was kind of my reward for doing this.
I saw every boy and girl that came for the demonstration, nude and on the floor. They all stripped slowly. The boys often fought the enema, but always lost.Of course an enema series was always give. Sometimes there were two or three boys being administered to. They all had to be nude together. There were a lot of tears and crying as the boys tried to cover their parts. The tears continued as the soapsuds poured in and as the naked boy pooped in front of everyone while the next boy got on his back. I learned a lot about teenaged boys anuses and private parts during these sessions.
The girls were a little different. First of all this only happened a few times, maybe ten. The girls enjoyed seeing me erect, but they wanted me out of the room when the got their enemas. No such luck for them. Panties came off and I got what every teen boy dreams of, a girl's outer vagina, anus, and pubic mound.
The girls took their enemas better. There was also another distinct difference. The boys were given enemas because their mom thought they needed one or because the mom was learning how to give them I only remember one boy getting a series because he was going to the proctologist/
Across the board, almost all of the girls were going to the doctor that day and the enemas had been requested by the doctor's office
In the background, the girl's moms talked to my mom about internals, rectal exams, speculums, and nudity in stirrups. While my attention was fixed on the enema nozzle firmly lodged in the girl's butt, but I was listening.
All of this made for some odd looks and interesting conversations in junior high.