Meet me Halfway
I mean, I got to enjoy tormenting their souls for a while before they could enter the gates of the spirit paradise if they were good enough and the spirit prison if they weren't.
But then there came the undead: those who stood between living and death. They get to have mortal bodies, but their real physical form would be left behind, buried and mourned over by their loved ones.
Precisely speaking, the undead were souls with human flesh.
I can easily tell them that, but it would be very hard to explain, so I go for the term undead, which they understood better.
They are scattered all over the world, actually, but most of them were almost invisible, which is where the ghosts transpire from, so