A few people have commented on how un-erotic they find restroom sex, perceiving it as filthy and disgusting. I basically agree, and have never engaged in such activity myself. I wouldn't know how. Yet I actually have a weird, erotic, fascination with restrooms, gang showers, and locker rooms, but no actual experience with sex in any of those places. It's a bit off-topic, but I hope folks won't mind if I explain my fascination with such spaces, and why I find them erotic.
My fascination with restrooms, gang showers, and locker rooms probably began in 6th grade, when I entered middle school. In elementary school, we had gym class in our regular clothes, but in middle school we had to go into the locker room and change into gym clothes. I noticed that in the back of the locker room there were showers plus some urinals and one or two toilet stalls. The showers both terrified and fascinated me. I had seen movies and TV shows where teenage boys (and sometimes men) had to shower together in the locker room, and I was really afraid we were going to be required to shower naked together. That would have been awful. I was picked on and bullied as a kid, and I expected there'd be a lot more of that if I had to shower with the other boys.
But, as it turned out, we were never instructed to use the showers. I was grateful for that. At that point in my life, changing clothes in the locker room was scary enough. But I don't recall the teacher ever saying anything about the showers, almost as if they didn't exist. In fact, I think it might have been a problem had anyone tried to use them, and there was no soap or towels available.
The shower area had two "rooms" covered with green tile. The outer room had showers on the back wall. The left wall was open to the urinal/toilet area. The front wall was open to the locker area. The right wall had a opening that led to the inner showers, which was as dark as a cavern because the lights in there were never turned on. Once or twice I may have been brave enough to actually go in there and take a peek around. Then again, maybe not. Such an action would probably have been noticed and (unfavorably) commented upon by the other boys. Nevertheless, I developed an erotic fascination with that space, with its mysteries, with what used to go on in there. In a bygone era, that room was routinely full of naked boys showering together! Terrifying! Exciting! Oh, how I would have liked to have been a fly on the wall, to go back in time and somehow invisibly witness the room in use (without being exposed myself). It just seemed inherently homoerotic, not that I knew that word back then. Part of me wished we used the showers so that I could have that experience, but mostly I was grateful that it wasn't required.
I used to fantasize about breaking into school at night, not that I would ever actually have done such a thing, so that I could explore those showers in private and maybe even use them--with no one else around, of course. If I could go back to my middle school and take a shower in that room (without any students around, of course), I might do it.
The showers in my high school locker room were never used, either, except for ONE incident. Again, the showers were a dark, mysterious, cavernous place in the back of the locker room that nobody ever entered. But that changed on one hot June day very near the end of the school year--possibly even the last day of gym class for the year. We had class outside that day. When we went back into the locker room to change before heading off to our other classes, one guy stripped naked and took a very quick shower. I didn't know him; he was just an anonymous guy in a rather large class. I guess he decided that he was hot and sweaty and wanted to wash off. His buddies gave him a hard time about it, and he was clearly a bit embarrassed by their reaction, but stood his ground. I actually thought the guy was rather brave. I also liked getting to see a fellow student naked--I'm pretty sure that's the only time that ever happened--but I was afraid to take a good look, lest anyone notice me looking. Everyone else kept quiet probably because they couldn't believe that anyone had been bold enough to get naked--in school!--and take a shower. It just wasn't done. I don't know how he dried off--there were no towels. The whole incident was over quickly, but obviously I never forgot it.
At some point, I started having recurring dreams about these huge, labyrinthine restroom/locker room/gang shower areas. When I was in college, I had a dream that I living in a large white house with a bunch of other guys. In the basement of the house was such an area. The space was old and run-down, but not filthy, covered with white tile walls and filled with broken, leaky fixtures, wet floors, and flickering lights. One room was full of free-standing urinals arranged in pairs in the middle of the room, positioned so that you were not only exposed while peeing, but you would actually be facing the guy using the opposite urinal. It was usually empty, but I liked wandering around and exploring the spaces. The place seemed to be full of ghosts of men pissing and showering and jerking off and having sex.
I had a variation of the dream recently. I was wandering some kind of old, abandoned factory--or maybe it was some kind of mill, like a sawmill or textile mill. Again, it was like a labyrinth--lots of corridors and stairs twisting and turning and seemingly endless. Some places were dark and empty, but fun to explore. But in other parts of the building, there was a rave-type party going on. In still other parts, people were having sex, both men and women, gay and straight. I ended up in some kind of restroom/shower area where a gay orgy was taking place, and ended up on my knees getting a golden shower from a hot guy. (That's something I've never done in real life, but in the dream it was as hot as hell.)
I used to travel a lot for work and have been in several hotels over the years. Some of them have intersting restrooms and pool/sauna/gym areas with erotic potential.
I'm also fascinated by European street urinals, especially old-fashioned pissoirs or vespasiennes.
I've never been to a bath house of any kind, either a gay bath house (where sexual behavior is expected and permitted) or a "traditional" bath house (for socializing and bathing), but I think I would like such a place. I don't think there are many places like that left in the world, and they are mainly in big cities, of course. There's nothing like that where I live.
Anyway, I've started collecting pics that remind me of my erotic dreams about restrooms and gang showers. I've got hundreds of such pics, but I'll only post a few of them here, since they are fairly off-topic. If there's any interest (which I kind of doubt), maybe I'll start a separate thread dedicated to the subject.
Re the pics below: I think the urinal in the gang shower is bizarre but brilliant. I also like how the pole/pillar style of gang shower forces 4-5 guys to stand in a circle, shoulder-to-shoulder, facing each other, as they shower.
