The yara-ma-yha-who lived in the tops of fig trees and did not hunt for food, but waited until unsuspecting victims sought shelter under the tree. It then jumped down and placed its hands and feet on the body. It would drain the blood from the victim to the point the person was left weak and helpless, but rarely, to cause the victim to die. The creature would later return and consume its meal. It then drank water and took a nap. When it woke, the undigested portion of its meal would be regurgitated. According to the story, the person regurgitated was still alive, and children were advised to offer no resistance should it be their misfortune to meet a yara-ma-yha-who. Their chances of survival were better if they let the creature swallow them.
People might be captured on several occasions. Each time, they would grow a little shorter until they were the same size as the yara-ma-yha-who. Their skin would first become smooth and then they would begin to grow hair all of their body. Gradually they were changed into one of the mythical little furry creatures of the forest.
The story of the yara-ma-yha-who was told to young children who might wander from the tribe, and to naughty children to scare them that it might come and take them away.