You know how a lot of people have the notion that anime and manga are over-the-top, ultraviolent, and oversexualized? Well, it's because of pieces like this.
It has the whole package: jump scares, gore, sex, melodrama and ridiculous plot twists. At heart it's the classical "a group of more or less close people are trapped in a walled space where a mysterious and unstoppable evil kills them one by one" horror story, but with everything turned up to eleven. The author has no shyness about showing human guts in a very detailed manner, time and time again; the deaths are gruesome, the villains are sadistic, everything but the little girls is dark and morbid. It also has an emotionally manipulative side, what with forcing you to empathize with cute and innocent girls only to eventually murder them in the cruelest possible way. This, my friends, is Dolls Fall.
BUT all of this doesn't meant at all it's bad; in fact, it's pretty good at what it does. It's thrilling, entertaining, atmospheric and very addictive. If you're into moe and/or gore and/or hentai and/or horror, you can enjoy it a lot: I know I did. Just don't expect anything profound, subtle or restrained. Read the first chapter, and if you can stomach it, keep on. It's so evil and twisted, but so silly and unbelievable, that you'll find yourself disgusted, scared and amused all at once.