Kingdom Hearts Divewing {ON HIATUS}

A young boy living in a boring and normal world gets sucked into the crazy universe of Kingdom Hearts, with only a familiar Key to guide him, he must travel forth and figure out what has been happening to the Worlds.
A Kingdom Hearts story, OC centered and it will consist of various crossovers between FF and some others, also I kinda want to hear what Worlds you'd like me to integrate in the story(If I know of course the world, otherwise I'll try to look into what you'll be suggesting and if I feel that I won't ruin that world and its characters then I'll try to put it in. For example FFXV, I know kinda of a big deal, but I haven't played and not planning to, at least not yet, so I can't put Noctis in because I don't know his character, save for the very basic that I got from a few videos I saw online.)
Its a story completely different than the KH, slightly AU, I mean, Some things in the games have happened and some have not and let's not forget that KH3 is around the corner(hopefully) so whatever I do right, it will become automatically AU when it comes, hence the AU tag :)
ALSOOOO big also.... there may be pairings even some boyxboy ones... just nothing explicit... otherwise I'd have to put it on Mature...