I would like to add something to the argument of Oscar and Ozpin, true at the moment they haven't merged completely, so for all intents and purpoes Oscar is merely possessed by Ozpin until the merge is complete. HOWEVER Ozpin mentions his immortality and reincarnation is the result of a magical curse, CURSE, inflicted upon him for failing to stop Salem in his original incarnation. Given that in most stories curses tend to be broken once certain criteria are met it stands to reason Ozpin's curse will be lifted once Salem dies. So what would happen to Ozpin if Salem dies before he and Oscar fully merge.

Will the merge simply continue and this will simply be his final life.

Or will Ozpin pass on and Oscar will be free to live his own life.

I'm not saying I support the Ruby x Oscar Ship but I am saying it might not be as sick as some believe.