This going to be short and crisp. I loved it. Beautiful concept and even though there are a lot of parts where you're just assuming things, I think that's one of the best parts about this manga. It keeps you guessing and on the edge! I definitely recommend reading this!! I don't think genres matter that much if you love a good story and have an open mind. You may need to keep an open mind while reading(can't reveal much because of spoilers). Characters were well rounded and the whole story just kind of fit together perfectly. I loved every single character and the best part wasthat even though there were the "bad guys", it was as if you couldn't even hate them!
It has a bit of gore and obviously has action and blood, but if you've read Tokyo Ghoul etc. it's not a big deal, really.

READ READ READ!! Guarantee you'll enjoy! :)