epples and benenes's feed

So that 4th ghost, that wasn't Touma, right? Because he said he didn't possess Yuma during the letter thing, so that was Touma that did that and not the 4th ghost. So there's actually 5 ghosts? Then where is it now? Or was it lying? Is Touma actually that 4th ghost? The panel where it showed the past lives, there were 4, but in some scenes we also see some other entity looming over them.