Gretka was a minor character in The Witcher 3: Wild Hunt. She first appeared during the quest Ciri's Story: The King of the Wolves, where Ciri found her on a tree limb looking down on three wolves below her. Ciri killed the wolves, rescued Gretka, and then accompanied her through the forest.
Gretka told Ciri the story of how she came to be alone in the forest. Gretka told Ciri she had lived in Lindenvale with her family. Apparently, her family was unable to feed her and the rest of the family, so as punishment for breaking a jar and losing all their milk, her father sent her out to "follow the trail of treats" and come back when she was full. However, she got lost chasing a butterfly and thus ended up in the predicament Ciri found her in.
Ciri watched over the girl until after their meeting with Phillip Strenger, the Bloody Baron. Knowing it'd be pointless to send her back to a family that couldn't feed her, the Baron allowed her to stay at Crow's Perch on the condition that she help out in the kitchen. In return, she had enough food to eat and a roof over her head.
- Gretka can be found inside the kitchen of the Baron's castle at Crow's Perch after completing the King of the Wolves quest.