Unusual - Characters do things that are strange and/or out of the standards of
original work.

I dono't think this a valid classification, really.  Most fics would have this
label.

DarkFic - I have no idea how to define this.

A story set in a normally bright and/or upbeat anime/manga which is focused upon
the death, mental breakdown, or secret or public unsavoryness of one or more
characters.  This should be distinguished from the "sadfic", which is rarely more
than a vignette, and shows the reactions and developments in the wake of some
tragic event that is out of character for the original story as a whole.  Here's
one way to look at it:  A sadfic shows Ranma mourning Akane's death.  A darkfic
shows him planning and executing it.

CrossOver - When two or more different series are brought together in one
story

There are two varieties:  the crossover, in which series 1 runs right into 
series 2, and their characters bum around together; and the fusion, in which
characters from series 1 take the roles of characters in series 2.  Fusions
can get quite bizarre.

-- Bob

-- 
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Robert M. Schroeck          || "When in trouble or in doubt,
rms@eclipse.net             ||     Run in circles, scream and shout."
http://www.eclipse.net/~rms || I have no mouse and I must scream.
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