The Heroro people of Nambia Africa believe when a sorcerer dies he’ll become a vampire revenant called Otgiruru (pronounced Ot-Goo-roo).
This vampire looks like a dog. . . a common stray dog. The villagers don’t pay any attention to the stray.
The Otgiruru calls out when no one’s looking. The person who answers the call will be its next victim.