The idea behind the story is quite obvious: There are too many strange things happening in our living world. Living people in the story are all unhappy, facing bad situations, and selfish. The dead are all the opposite, happy, look in the bright side, helping each others etc. The song of the deads when the first time Victor meet them have told how positive they are: “Die, die we all pass away. But don’t wear a frown cuz it’s really okay”.
Another thing that is funny: Even when the dead want to punish Barkis, they need to wait until Barkis die. It seems want to tell that even justice, can only come not in our living world.