Demon anime please!

Here's six I can think of:
Nura: Rise of the Yokai Clan (Picture)
InuYasha/The Final Act
High School DxD (Mainly since the main characters are Devils but still Demon but in higher power)
Devil May Cry (That's a anime)
Devil Lady
Demon Lord Dante

Ao No Exorcist (Blue Exorcist)

demons animes are awsome

Kuroshitsuji! Its my favorite anime, and you'll be drooling over Sebastian! 😉

Higurashi no Naku Koro ni involves demons. But it's very gory, profane and well....just plain out psycho.

Rage of Bahamut: has demons and angels and cowboys and shit

devil is a part timer its really funny

Some of these cross the line between Yokai and Akuma (spirits, demons, creatures) so I don't know how demon specific you want to have. Or if you want darker or lighter versions but here's a few options. You could probably google picture search them and can tell pretty fast if they are what you are looking for or not. Hope it helps!

Natsume Yuujinchou
[pictured] Saiyuki
Ghost Hunt
Amatsuki
Otome Youkai Zakuro
Inu X Boku SS
Noragami
Devil May Cry
Psychic Detective Yakumo
07 Ghost
Blood Lad
Yu Yu Hakusho
Hakkenden
Kamisama Hajimemashita
Hakuouki series (in order: Hakuouki Reimeiroku, Shinsengumi Kitan, Hakkesturoku, Sekkaroku)

"Gegege no Kitarō". The franchise is REALLY popular in Japan, but surprisingly unknown here in North America

To recommend a cute newer show that not many people have heard of/ seen: You could try Hoozuki No Reitetsu

Inu Yasha

my newest obsession: Devil survivor 2 the animation

Here's a few:
Rosario+Vampire (haven't gotten into it yet but I've looked at it and there might be some demons in it. Idk.)
Blue Exorcist
Inuyasha
Black Butler
Soul Eater and Madoka Magica (as well as other Magica series) are more witches than demons, but the witches in this are like demons.
I guess Bleach would work as well, but I don't know. I recommend it, though.
Another I recommend, though it doesn't have demons but something kinda similar, is Fullmetal Alchemist. I prefer FullMetal Alchemist Brotherhood. It goes by the manga.
I hope that helps.

Machikado Mazoku