This manga is something exceptional. It surely isn't for everyone, as it's humor is pretty weird and the story is just erratic. However, if you stick with it, you'll realize it's actually great.

Story-wise, it's weird, honestly. The manga is basically all of the genres; it ranges from comedy to even horror (!) and psychological thriller sometimes. However, it handles each part so splendidly that you won't notice the conversion from funny and weird to serious and unsettling. Yuusei Matsui really did a great job. Also, it does cover many mental states via the villains and several characters. And it does that pretty nicely. Other than that, the story consists of four basic arcs;

1) the first part (up until chapter 60) where there are many, separate cases that don't connect with each other. It's basically an intro for the characters and some development. Also, they do introduce the main villain, who doesn't do anything exceptional.

2) the best arc. A new villain appears and decides to rule the world. The thing is, it doesn't get boring at all, the motives and continuation are perfect and the arc ending is so satisfying. You might even get emotional.

3) the main villain starts to do shit and the protagonists have to stop him from completing the said shit. Pretty great, I sadly cannot say anything that won't count as spoilers.

4) the last arc, where the final, true villain appears and does worse shit than the main villain. The thing is, some situations really do cause anxiety and/or disgust on a whole new level. The ending is pretty generic in my opinion, but I weirdly didn't mind. It did leave a lot of possibilities open, so that might be why.

The characters are all great, with more than enough development for each one of them. This manga is one of the cases when you just cannot hate any one of them, no matter how evil they are. Even supportive role characters that do seem useless are pretty likeable. As the story progresses, some of them die. And that sucks. A lot. I even shed several tears for one of them. Other ones got injured pretty badly and I was in pain, just like them. They are just so realistic that you can't help but care about them.

The art was the only difficult part to give a score to. It's kind of bad, especially in the beginning. However, it does get better later on. The thing is, there are some certain parts that are handled PERFECTLY. The meanings, the absurdness, the comparisons are shown the way they should. The art there is just exceptionally awesome. I cannot really describe it, you'll have to find out what i mean on your own.

Overall, I enjoyed it very much, although I felt like it would get kind of boring mainly at the beginning. My advice is, don't stop it. Clench your teeth and keep going. It'll be worth your time later on.