Ok this story is pretty creepy and the twist at the ending... DID NOT SEE THAT COMMING! 
 I went through a few stages with this: 
 - At first I thought it would be the story about the human eating trees Tamar was telling us about in Ruin and Rising, 
 - Then I thought that Karina is the witch, 
 - And lastly I thought it would all go on like Hansel and Gretel. 
 Which of these hypothesess was correct? 
 Well read it yourself and find out. ;)