I think this book deserves a 50/50 rating, not because it is a soso book, but because of the polarising emotions I have towards it. 
The study of grief is excellent, and the demonstration of a young mind's decay into fear and uncertainty caused by an exposure to death is well done. 
The motif of the coat and Jas' baggage was incredibly well done, and I find the ending to be fitting for the story and I see little other conclusion. 
That being said, with some books as this, that try and push 'deeper and darker' I find as if they attempt to create the most dark and gruesome stories even when it makes little sense.

Obbe's incest, rape and pedophilia is not handled in a way that makes it woven into the narrative. It just creates squirming and horror at what is happening, goes unresolved and doesn't seem to fit with the fallout from Matthies' death to me that well. While I understand the implications of Jas' curiosity, many of the passages involving rape and incest seem jagged and unnecessarily dark just to remain in your head.

. While it may be a good book with incredible writing - what I have taken from it is not it's best features, just the shock horror value it attempts to reel you with, and that is a shame to me.