Main conclusion: not brilliant, but certainly a good read.

story;
A girl (Yako) whoes father was murdered comes across a deamon (yes, it is consequently spelled as deamon) aka Neuro that solves the 'riddle' of this unsolved case. Neuro feeds on riddles and he wants to eat riddles from the human world. He uses Yako to navigate through human society and makes Yako a famous detective. Her role within their detective agency is mainly to smile friendly and keep close contacts with the police.

The first 60 chapters are short stories. Of course there is a big villain (X), but he's in the background. The short stories are all about a murder case where the murderer tried to hide he did it through a 'riddle'. There were several riddles that were way too far fetched, but overall it was nicely done.

After the first 60 chapters of only short stories there comes another big villain comes along: A computer virus that turns people into criminals. This keeps us occupied for another 30 chapters.
So after about 30 chapters containing a bigger plot we're back to short stories.
X gets a bigger role and appears more. Short stories, with a red thread concerning the cat and mouse game that develops between X and Neuro - we're heading towards chapter 120.
It turns out X is only the beginning of the trouble that awaits. There is a super villain responsible for X. This villain and his evil plans will be the grand plot of the story. So it is 80 chapters only the super villain and his minions against Neuro and the police squad.

The switches between little stories and the main story are, in my humble opinon, too big. When you read this manga in one go, somehow it doesn't feel good. The way how people from different stories fit to gether in the bigger picture manga is nicely done.


art;
On the first glance you'd say Matsui-sensei's art isn't worth mentioning. You couldn't be more wrong. When you look closer at the art you'll be pleasantly surprised. It is clear that Matsui-sensei likes art and he shows this in multiple ways. For instance trough a story concerning a artist. The sculpture Matsui-sensei has drawn for this story was awesome.

Matsui-sensei's drawings are clearly based on several artists. Neuro's deamonic form for instance, reminded me somehow of the creatures in the paintings of Hieronymus Bosch. Other deamonic things had aspects you could defenitly link to Dalí. Several pictures (with Neuro sitting on the ceiling for instance) were obviously inspired by the works of Escher. Matsui-sensei is also clearly into (Picasso's) surrealistic cubism.


character;
The characters evolve. You can see they really change throughout the story. Some don't change for the better. This way it is realistic. I also like it Matsui-sensei doesn't have too much trouble with letting characters die.
However the way several of the murderers or the supervillain are portrayed is far beyond realism.


Enjoyment:
It was a nice story to read. I liked it, but I can't say I loved it. The comic relief was nice. Neuro's sadistic traits were funny, and Yako's eating habbits were hilarious. In the translator notes I read much jokes were untranslatable because the jokes were in the kanji readings. Too bad, it would have made the story even better.