When will people stop comparing every demon/spirit manga with Yu Yu Hakusho?There are lots of manga with demons and spirits. Japan breathes demons and spirits. Just because it's underworld related doesn't mean it's like Yu Yu Hakusho.
To me it sounds similar to Urotsukidoji, seeing how thats three world's Human, Demon and Man-Beasts in the Anime and just the Human and Demon in the Manga without the Hentai crap that came with that paritcular series. So you may be right in it being something that might take one's interest.
I also concur with what you have said with Yu Yu Hakusho. Despite what people think it wasn't all that great of a series, personally I think its was over-rated much like this era's Animes such as Bleach or Naruto for example.