The Soul

From Slavic.info

The soul can leave the body in sleep and enter another person, called Mora or Kikimora; and the soul (Sjeri) often acts as a household spirit. In Serbia these souls (Zduh, Zduhacz) battle for the welfare of their owners. After death the soul remains on earth till the corpse decays, and during this time food and drink should be offered it. The souls of sorcerers may become Navky, Rusalky, etc.