Board Thread:Boruto: Naruto the Movie/@comment-6232909-20150811172020/@comment-24729606-20150820221742

Well I can't say that I relish the thought of that demon Orochimaru having descendants to carry on his depraved name but it makes sense but I have another, much more in character, possibility. I theorize that Mitsuki is one of Orochimaru's test subjects (like Karin, Suigetsu, Jugo, and Kimimaro). As for their similarities in appearance and abilities that's easy enough. Orochimaru's goal remains to unlock every jutsu their is so its not out of the realm of possibility that he would also want to develop new sage arts too, after all his research on Jugos clan lead him to Ryuchi cave where he hoped to learn senjutsu. He does seem to think that only jutsu involving hand signs qualify as jutsu which means that the number of jutsu would be roughly 479 billion. As for the whole extendable limb thing well if he could do that himself he would probably want to develop it further and his normal answer to doing that is to conduct his experiments, which (as he himself admits) use up a lot of test subjects. Although it's also possible that Orochimaru's eyes are a kind of kekkai gengkai which may mean that Mitsuki is a member of whichever clan Orochimaru belongs to.