As in, not all these high school comedy\harem thing that has a girl as main character or a main romantic interest, and is a monster or the boy is surrounded by female-monsters. I want a manga where the guy is the main lead, a some type of monster (or... deity? god, anything not human, I guess), has MALE friends (not a bunch of girls following him) and is in some kind of school settings...

So Manga like Rosario to Vampire or Vampire Knight doesn't cut it. I'm just tired of all the "harem\comedy\romance\clumsy+cute+popular+pretty+cool+And-Oh-Look-She's-Secretly-a-Princess\Monster\Vampire\Whatever type of character.

Fukigen na Mononokean
Satou-kun no Juunan Seikatsu
Makai Ouji - Devils and Realist
Goraihou Gakuen e Youkoso!
Eerie Queerie! and Gakkou no Sensei, provided you don't mind (very mild) shounen-ai.

Youkai Gakkou no Sensei Hajimemashita! is a good fit, too; sadly, though, it hasn't been scanlated into English.