It's an exact plot ripoff of Dead Like Me from Showtime....and technically they already MADE a movie of it....
but seriously, this plot doesnt even TRY to be at all different from Dead Like Me:
Guy dies....finds out he's now a grim reaper and has to catch the lost souls of others who have died and dont know where they are. People can see him, but he looks different than his actual appearance that way people he knew dont recognize him.
all they did in this movie was make the lost souls into demons. its literally an exact clone of Dead Like Me.
Oderint Dum Metuant