Board Thread:Naruto 7: Discussion/@comment-4437326-20141101231856/@comment-24847491-20141103015533

He has probably gained immortality, also somebody on Tubmlr theorized he needs a Hyuga to act as the catalyst to revive Kaguya into. My guess is, he's Hamura and Hagoromo's brother and if Kaguya was revived she would probably kill Toneri and take his chakra anyway