This Mystery is Already on the Tip of My Tongue

The next series I will be citing is a bit lesser known. It was never published in America unfortunately, but people (who should be considered for sainthood) have translated all of it's 202 chapters into english. It was also turned into a 26 episode anime series, which was also very good. It's title: Majin Tantei Nōgami Neuro, Demon Detective Neuro Nōgami. The title is pretty much the premise of the story. There's a Detective named Neuro Nōgami, and he's a demon.

The series' protagonists: Neuro Nogami (Left) and Yako Katsuragi (Right)
[Source]

The series follows high school glutton student Yako Katsuragi, who is plagued by the mystery surrounding her father's death. One day she meets a strange man who stands upside down in midair (Trust me, that's fairly normal) who offers to solve her mystery. You see the man, Neuro, is actually a Demon. He literally lives off of mysteries, and when a mystery has a "puzzle" to it (like a complicated plan, usually to a murder), the mystery gives off a stronger scent, and becomes more nourishing. Yako agrees, and for the rest of the series, Neuro pretends to be a normal human to get closer to these mysteries, and he has Yako pretend to be his master, and the real detective behind solving all the cases. They develop quite a reputation, and meet many interesting people along the way (allies and criminals alike). The violent and tortuous antics Neuro pulls on Yako are an ongoing joke, as well as all the strange qualities the Demon has. A very fun read indeed.

This is another of my personal favorites, as it is a mystery comedy, much like some of my favorite TV shows (Psych and Monk to name a couple). The hilarity of Neuro attempting to appear human, while forcing Yako to do his bidding (often through hilarious but serious threats) makes this series a nonstop laugh riot.

Matsui, Yūsei. Majin Tantei Nōgami Neuro. Vol. 1. Tōkyō: Shūeisha, 2006. Print.