He could be another tailed beast? Wasn't Hidan and Kakuzu etc around the temple looking for one before they stumbled upon the Monk and Asuma????
Good prediction but imo it's a tailed beast, one we don't know about.
in reference to your prediction yo!!! MUst be Sora they were after.
Maybe he's the 8 tailed... seing the relevance to other material as the 9 mythical beasts.