Angel Sanctuary is a manga series by Yuki Kaori. It revolves around a high school student named Setsuna Mudou. He's also the current incarnation of Alexiel, the organic angel. As such, like all of Alexiel's human incarnations, he is destined to die a violet, painful death. He's also the Messiah. Setsuna is desperately in love with his own sister, Sara. The story also revolves around other angels, including Lucifer, Michael, and several others, though few are what you'd expect. Setsuna is a "trouble maker" who gets faint at the sight of blood (this is later explained). He knows who he is and is more concerned with Sara than his destiny.

The manga series was published by Flower Toyome Comics. There are also two artbooks, Lost Angel and Angel Cage, as well as postcard book called Angelic Voice.

There is now an OAV series out as well. It's 3 parts and has been picked up by Central Park Media, so it will come to the US soon. From what I've heard, the OAV is most the events of the manga (though some are out of order) pushed together to get the story out. Basically, it's just the jist of the story, but would be good to see if you'd like to see the characters in anime form. I'm hoping someone will make into a TV series, but since it's already an OAV, I'm not sure how good those odds are. (Although several series started as OAVs and ended up as TV Series: Vampire Miyu and Record of Lodoss War to name a few.)

The thing that draws in most fans is the artwork. It's extremely detailed and gorgeous. What keeps people as fans is the amazing story, the twisting plotlines, and the realistic characters. You may also notice that some of the pictures seem to have sprung up from an episode of Hey! Hey! Hey! Music Champ (a Japanese battle of the bands). If some of the make up or clothes reminds you of your favorite J-Rocker, Yuki Kaori is a big J-rock fan. ^_^