Title:  Ouran Academy Guest Lecturers Series
Fandom:  Ouran High School Host Club, crossover with: Fruits Basket, Gravitation, Yami no Matsuei, Love Mode and Skip Beat
Pairings:  gen, although some hints of canon pairings like Yuki/Shuuichi
Categories:  crack, humor, crossover
Length:  Medium [10,000+ words]  Bonus rec!
Warnings:  hints at (canon) incest


Author on LJ:  n/a
Website:  Her page on Fanfiction.net

Review:  What Ouran Academy really needed to become even crazier than it already was, were week-long visiting lecturers.  

I'm a little leery about reccing the entire series, simply because I am only familiar with the first three crossover canons.  Nevertheless, each chapter stands comfortably on its own, and I do recommend the first three chapters without reservation.  To summarize: 
Chapter One: Fruits Basket is such a shoujo series, that having it collide with Ouran (which may be shoujo but certainly spends more time parodying it than playing the tropes straight) was a stroke of genius.  Shigure's interactions and musings about the Ouran students were delightfully in-character, as were their reactions to him.  I particularly liked his attempts to bring out "Black Mori".
Chapter Two: Yuki as a willing guest lecturer is a harder sell, but his more cynical nature acts as the glass of cold water to the face that Ouran characters desperately need.  Plus, it's at this point that a certain thematic repetition starts to become apparent.  Namely, that the lecturers will a) determine that Haruhi is a girl, and b) be able to tell that the twins are faking their incestual relationship.
Chapter Three: Muraki should never have been allowed past the doorstep of a high school.  The reader knows just what he's like, and there's a dark humor in seeing the Ouran students get creeped out while remaining ignorant of his crimes.
 
I am confident that the remaining two chapters are also comedy gold, and personally enjoyed reading them, but I can't be certain that the crossover characters are as in-character as the first three lecturers were.  Then again, the series does not have an ongoing plot as such, and the first three chapters stand as a great medium-length story.

Ouran Academy Guest Lecturers Series