If the fic is NC17 in any part, you should post it to the adult community, bymoonlight. It protects you and everyone else that way. Under-age people can always find the fic in your own journal, too, if you post it there, and you can save the NC17 coda for bymoonlight.
Thanks for asking! *HUGS* Also, long fic? Rock on! Post soon, ok? *grin*