I´m a huge fan of gore and psychological manga. This manga has both, gory and psychological aspects. I´m not a big fan of lotsa text, but some points in this manga are kinda "chewy". You don´t really feel like reading everything.
But even if this is one negative point, the art makes up for it. I really like the art style and the details, as well as the nice design of the Ajin(Demi-Human).
The characters are all pretty important, and they all appear several times, you learn something new about them everytime they appear. I also like that the characters have a yet so simple, but unique design, you can recocnize them pretty well.
In my opinion this manga is lika mix of the manga Pupa and Tokyo Ghoul, but I wouldn´t compare these three manga with each other.

I recommend this manga for people who like a kinda realistic artstyle, with lotsa blood, betraying, screaming, deaths and sure, some sarcastic supernatural creatures.