The analogue of the real world
The pictures of the other world may fully copy the real world of live people with the villages, where dead people live with their relatives, get married and sometimes even give birth to children. Sometimes myths even copy the landscapes and the environment of the real world. The spirits are not immortal but in the other world they usually had the longer life than on Earth. Such beliefs are proper for the mythology of North-American Indians, tribes of Africa. With the lapse of time spirits die finally and are reborn as the live creatures on the Earth.
The spirits of the ancestors live in the other world until the progenies keep the memory and honour them. In the traditions of Bantu, the souls of dead people live in the other world until they get old after which gods drive them out of the other world to the earth where they turn into the ash.
In some primitive mythological systems the other world is the simple continue of the earth and this system has no opposition of the soul and the body. This opposition also varies in mythology of different countries in developed systems of mythology. For example, the Greek souls of Aid wanted the blood and were afraid of the sword. The Scandinavian souls kill each other and reborn in Valhalla. And in such way another opposition appeared that was reflected in the physical fight of the other world and the world of live creatures.
When there is the day on earth, there is the night in the other world, when live creatures have summer; inhabitants of other world have winter. Dead people walk head over heels and wear the clothes inside out, besides, their food is poison for live people.