'''Curator's Note:''' Please make sure the example actually fulfills the criteria of this trope(a party/social gathering that turns into an orgy), and try not to make it too explicit.

This troper once managed to attend a "housewarming party" with a dance troupe and their support staff. The house was most certainly warmed.

This troper accompanied some friends to one of those anime conventions (though not a fan of anime myself, I wasn't about to pass up a weekend partying at a fancy hotel with my buddies). One of the nights, one of my friends brought a girl back up to the room, and they just started going at it. With all of us right there in the room. After a few awkward minutes, some people decided, ''Hey, why not?'' and jumped right on in. The few of us who chose not to participate spent the rest of the night downstairs in the hotel bar until the ... fun was over. Needless to say, I haven't been to any more anime conventions.

This troper went to a party like this with his then-girlfriend. He came ''this'' close to sleeping with said girlfriend's IdenticalTwin. Seriously. The only reason he didn't was a) the twin had had too much to drink and passed out on top of him and b) his girlfriend was standing not three feet away doing her best not to die laughing.

There's a reason the SocietyForCreativeAnachronism is nicknamed "Society for Consenting Adults."

And other LARP & Re-enacting groups.

As a feeder, I feel pretty much like this every time I cook for a dinner party (which is often). More literally true whenever I'm dating a feedee who also gets turned on by my cooking.

Back in high school, this troper used to belong to a group of friends of about 15 people, and we would often all hang out together at the same time. Mostly in members' basements. We would often spend the entire time hanging out in our underwear. Once, we even, yes, all 15, decided to play strip poker completely sober.

My former high school's freshman class was already notorious for these when they got there this year. To boot, ''they all look twelve''. {{Squick}}ed yet? I sure as hell am!

This troper's friends tend to have rather... sexually charged sleepovers. Truth or Dare seems to exist for the sole reason of getting everyone out of their clothes, making out, or both.

This troper once participated in a PICKNICK that turned into an orgy. WTF?

Happened at an anime convention in Atlanta last year. Luckily for me and my girlfriend, I paid for my own room and avoided the orgy. All I know was some of my friends got more than they bargained for the morning after.

This troper has never been much of a party person, but she lives in a big house with multiple roommates. At one memorable shindig that didn't break up until the crack of dawn, she and her boyfriend were...um...harmlessly amusing themselves in their own bedroom when someone ambled in looking for the bathroom. Neither she nor he were best pleased.

I attended one party in college which involved multiple three-way all-female makeout sessions followed by a five-way (three girls and two guys) makeout/grope session. (I admit to having participated in a couple of these, including the last). Not long after, I went to another party consisting of fourteen people jammed into a tiny single dorm room. . .seven of whom, again all female, had an orgy on the bed. (I was NOT involved; I just sat on the floor drinking with the non-participants.)

This troper lost his virginity at one of those. While he was {{Shotacon underage}}. At age 14-16 he was in a band that played at the older years parties. The older years thought it was hilariously funny to get he and his bandmates (16-18) very very drunk, and eventually the parties took their usual course and he and his bandmates were invited to join. Now I'm older and in university where these seem to happen with slightly more regularity, I've basically lost my appetite for them.