In my theory it works just like it works with human. For time being i will refer to them as Ghosts. So, what i believe is that they also have a society, a government, family and all. They also have criminal minded and good beings at the same time. The criminal and mischief minded come to haunt while the the good ones try to be helpful and always come in peace and calm. There are many possibilities. It all depends on our imagination and what we try to postulate.