Sss, sss, sss! I'll take that as a compliment.

Well, what if he's strictly speaking not a ghost? He keeps talking about being in a room with 'white walls' and getting 'injections'. He could have survived, technically... as some sort of psychic burn victim. Trapped in a mental prison that he's lured us into. Kept alive only by a nurse.

You know, like in that horror movie.