From: Princess Melee

Didn't someone write a WORLD OF DARKNESS crossover called "Nerima After

Dark"?  It was part of a series of stories called Elseworlds, named
after DC Comics' alternate universe books.<<

That's right. I remember the fic, even if I couldn't remember its name.
There's also another Ranma/Mage x-over, incomplete, that was posted a while
ago.