It's pretty simple. In this format:
{his name} met {her name} in/on/at {where they met}. He said {"statement"}. She said {"statement"}. They {what they did}, and {the consequence}.
Write out a sentence using only one fandom. There's no limit to what fandom you can use; you're allowed to use any fandom you like, whether it be anime, game, books, comics, whatever! Also, you don't have to keep switching fandoms in every post if you don't want to, but it'd be nice to have something different, ne? If you run out of fandoms you want to use, then you can reuse an old one.
For the "what they did" and "the consequence" parts, you can write anything. It doesn't have to be a certain event from your fandom, but if there's some funny moments in your fandom and you'd like to use those then by all means go ahead! Same goes with the "where they met" and "statement" parts, but using venues and quotes respectively. You can make it as funny, sexual, violent, etc as you like. Let your imagination run wild!
Generally what you really have to do is, in a group, write the first thing down ["his name"], then pass it around to another person. Then everyone writes the second thing ["her name"], then pass it around and write down and so on, because then by the end of it you get some crazy sentences! But I thought it'd be hard to do that here unless people want their PM inboxes spammed or something.
Anyways, I'll start with Naruto as a test run.
Naruto met Karin in a random jail cell in Konoha. He said "Give me all your butter." She said "Burn my shorts with Sasuke's fire." They popped champagne bottles and everyone else in the shinobi world died from heart attacks.
Yeah, lame, I know. You don't have to make the whole sentence italic/bold, I just did it so it's easier for people to see. Anyways, I'm pretty sure you guys can come up with something more creative than this.
Now, LET THE CONSEQUENCES BEGIN!!