He is feeling pretty badly about himself due to a bullying incident which took place at his school back home.
The village in which his sister lives is rich in folklore and strange stories, which soon become more than that to John.
I enjoyed the myths in this story, especially the one of the strange black dog who will lead one to safety.
In a way, this is a coming of age story, in another way, this is a story about facing one's fears.
However one chooses to view it, it was a good story.