I feel like this show was hard to root for. I really wanted to like it, because it had such great and interesting concepts, but I think the director failed to make the concepts work. It was all dumped on you, and rushed. I also feel that the show lacked an identity of what exactly it wanted to be. Was it a horror show? A harem? An action show? A psychological show? A show can be all of those and still be great, but here they just didn't connect them very well. Most of the show just seems like a plot dump, followed by school filler, then Takumi going from girl to girl just to talk about more concepts. The worst part is that there are only like 2 episodes left, and they are still introducing new concepts.
As you can tell, I love the way they told this story. If they had a 20 in this section, I would give it. Now, I will tell my reasons.
You already know that this was a great thriller, as it keeps one guessing right up until the end. And your interpretations of the characters change on a pretty constant basis as the story progresses. Here's an example: I first hated Takumi, but at the end of the series, one could only feel jealous of the ------- with a certifiable harem of great women and the powers of a god. Perhaps this is all a little exagerated, but I think my point was made rather readily with that.
Thriller anime are either great or they suck. This was one of the great ones that came with a few bonuses, including some pretty good backstory and backworkings within the story.