The mystery keeps bigger and bigger, and eventually reaches an unorthodox conclusion.
There are two issues with this manga, however.
First, the beginning of the story (first 10+ chapters or so) is MUCH stronger than the rest of it, as plot starts unfolding, at some point it becomes less coherent and deals less impact, which is why it is 7 and not 9.
The second thing is that the art takes some time to get used to as it rather unusual. The manga heavily uses lineart drawing with minimum shading, which is different from many other works. As a result in the beginning it comes off as simplistic, or even amateurish. You very quickly stop noticing that, though.
Breakdown:
Story: 7/10.
Starts very strong, gets weaker, but still delivers. Over time it becomes less "realisitc" and more "fantastic", but it remains servicable.
Art: 6/10:
We have unusual style here, focusing on lineart and with minimum shading. Side effect is that this style makes smiling faces a bit ugly. It is not horrible, and you quickly get used to it, however.
Characters: 7/10:
Very life-like characters, especially in the beginning. No textbook cliches here, as far as I can tell. Feel like real people for a good portion of the manga.
Enjoyment: 7/10.
Liked it.
Overall: 7/10.
Worth a read. I think if you read Uzumaki by Junji Ito and liked it, you should enjoy this title. It doesn't quite feel Ito's level, but gets close enough to be enjoyable.
That's the rough idea of it.
