I'm a big fan of ghost stories and stories from the POV of "monsters," so those elements worked really well for me. This is quite dark, though, and the pacing/plotting is a bit strange and erratic. In some ways it almost felt like a series of short stories (or short horror movies) connected by the same POV character, with diversions from the main plot that never seemed to make it back around to being relevant. 

I think the narrator did a great job maintaining a narrative voice for Okiku, particularly the sections where the ghost's thoughts are more chaotic/intrusive.