It sounds like some kind of ability, or superpower, or wish, I dont know in which category I would put it, but here it is: When somebody dreams about me after I died, I would appear before them, and have a talk with them. Any kind of dream matters. If they are mad at me, I would try to apologize. If they miss me, I would give them a hug. If they dont understand why I said something,.or behaved in a way, I would explain. After some time, or eventually most of the people I know will forget me, and if nobody remembers me amymore, I will eventually go to the afterlife.
Its just that a lot of novels about ghosts explain the phenomenon in a way that ghosts who stay with us, still have business here, and have to tie up loose ends so to say.