well.. what's the link between them? Oro recodnised (spelled totally wrong but hey..) naruto's eyes, no doubt about it he tought... so he knew kyubi, and that must have something to do between him, the sharinghan from kakashi and also something with Itachi

so... what do you guys think it is?
I think he is a demon, and he knew kyubi, because after kicking naruto's ass he says ''naruto's and kyubi's chakra are beginning to merge, but right now you are in the way'' I think he wants to take over naruto''s mind and sasuke's 2, maybe everyone is linked in one big way, and only Oro and the fourth now about it..

*edit*

or wait what if that freak show did some sick stuff to naruto's mother just after he was born (that would be logical if the 4th was his father,since anko said something about the fourth and Oro hating eachother or something like that) and did sick stuff to his mom, maybe put an old demon inside of here and make here become kyubi and that wouth also explain why the fourth gave his life, since it's his wife ánd he is the reason she turned into kyubi