These are some fanfics I found on tvtropes.org, when I was bored one day and lurking around on the site. I found four that you guys might be interested in. They're all of various skill in execution and humor, and some of the concepts might be hard to understand, but I hope you guys enjoy them.
Those Lacking Spines, by Gexegee/Organization VI (meta, parody, crossover)
Synopsis: Thirteen chapters of traveling to parody worlds of all the worst excesses of various Fan Fic genres starring the three least-ficced members of Organization XIII. The parodies run, roughly in order: Uke, Slash Fic, High School AU, Self Insert Fic, Possession Sue, Canon Defilement, Intercontinuity Crossover, Crack Fic, Dark Fic, bishonen and of course Mary Sue. Somehow fits in some inexplicable Author Appeal in the form of Moulin Rouge. It's got No Fourth Wall and self-conscious Author Filibuster, with Hypocritical Humor softening the Take Thats.
[If you didn't understand the terms tvtropes used, that's understandable. I had to look up most of them too.]
Am I Heartless, by Jazzerman
Synopsys: Twenty-four chapters that take place after the story of Kingdom Hearts II. Sora and Riku are back in their own world with Kairi and come across a newcomer to their world who possesses Heartless traits. The discovery of who he is, how he came to be, and what happens next is one for you to find.
A Sorrow of Magpies, by Luc Court
Synopsis: A Sorrow of Magpies shows the formation of Organization XIII, mostly focusing on Vexen. It starts with the formation of the original six, and the formation of their base, then gradually adds on the newer members.
[There's only one 'scene' that has any mention of 'sex', but it doesn't go in depth, and it's only to develop characterization.]
Kingdom Hearts: The Short and Honest Version, by NCHammer326
Synopsis: This can basically be described as Kingdom Hearts: The Abridged Series. Essentially it parodies everything about the first game, with Sora as the Only Sane Man who is Surrounded By Idiots and Jerkasses (or by his own words, Tools or Douches).
[It's not actually bashing the series: it's just twisting the situations Sora encounters in a humorous way. Really. Oh, and this is the only one written as a script. There's also a gratuitous amount of swearing, but that's supposed to be part of the humor.]