Well the ending with why Satoshi died is still a big mystery to me. He died because he used a different piece, but if he gave his to Naomi then why not her also?
They showed Naomi in the end, but not Ayumi, I guess she lived happily ever after?
Other than that, I kind of liked this for what it was in the time it had. If only this got a full adaptation or something so I could fully understand it. Well, there is the game, but I'm not as interested in playing a game for a story.
This did pretty well as a horror, the brutality reminded me of Another. I think if it had more time, the plot also wouldn't be a confusing mess. Either a 6/10 or 7/10 for me.
I liked the Kishinuma and Ayumi thing ;)