Not sure about other races but correct me if I'm wrong, for us Malays, usually its called Saka. When the 'owner' dies, the 'being' will usually find a suitable host. That suitable host can be either be your direct family members or relatives that are really really close to you. Usually its the former. If no relatives, then I think it will go astray and hook to someone else that it deems fit?
Unless the new hosts accepts the 'gift' directly, the new host won't know it until he / she 'sakit' or acts differently. I remember my mum used to tell me that my late great grandfather or one of the uncles (same level) came into a dream and wanted to give something to her. In that dream she usually refuses it. At that time she already know that that person already practice the 'dark' arts.
Older malay generations use to 'bela' or 'amal' these things usually for war, as a protector and etc. Either you go the holy way or you go the dark way. Dad said that one of my late great uncles practice this. He has the ability to morph into a tiger (Harimau jadian). Purpose is to scare people or enemies from harming his family and property. Not sure if my late great uncle has 'thrown' it away or not. What usually worries and pities me is those who you do not know practice or keep these things. When they die, one of the family members get it unless the person throws it away before death. Expelling it also not that easy.