back on the Old Site there was r/195 which was somebody's apartment number and started out with just their friends. then it got popular, was flooded and became hard to moderate; the mods shut it down in what was known as The Experiment. This was the birth of r/196, which thrived before shutting down the second Reddit API shit hit the fan. And so here we are, on Fedi.
The main rule was that if you visited the sub you had to post a meme before you left, (obviously unenforceable) but that's why all the posts have "rule" in the title. It ended up being a very queer friendly and fairly horny subreddit, somewhat notoriously so lol