Although this is ostensibly a ghost story, it fits the genre of mystery more easily than the genre of horror.
The narrator, Harada, is a recently divorced TV script writer, coming to terms with his loneliness. He is deadpan and analytical in his delivery. Some of the phrasing does seem a little staccatto - and I see that another reviewer found the sentences rather complicated. I agree. It reminded me, if anything, of Sheridan LeFanu's victorian gothic mysteries - written at a time where ghosts were to be investigated and understood rather than feared.
The storyline is certainly odd: Harada meets up with his long dead parents and visits them for tea. Although he knows it to be wrong, his curiosity drives him on. Meanwhile, the rest of his life and relationships rapidly take a turn for the worse. The novel (novella?) perhaps suffers from brevity. With more space, the characters might have been enlarged a little, and perhaps the narrator made a little more likable; a little warmer. Having said that, the story does move on apace and this takes attention away from the lack of empathy with Harada.
The cover talks of a bizarre twist. I'm not sure it is really a twist - it is pretty obvious from early on that something is not quite right. One is left guessing what exactly it is that is out of kilter and I suppose the revelation does have some element of surprise. It's hardly a twist on the scale of The Crying Game, though.
Overall, the book was a good read. It managed to hold my interest but without being exceptional. I don't think I gained much insight into either Japan or the supernatural but at the same time, it was as good a way as any of passing a Sunday afternoon.