Kira
Kira is introduced to us as the older classmate and best friend of Setsuna (Angel Sanctuary's pretty but troubled protagonist). Kira is clearly a rebel- he hangs out in underground places, has shady companions, and generally looks like a bad boy. However, he's frequently reading, coming to Setsuna's aid, and exhibits a maturity that hints at something more.
Personally, he completely won me over during his monologue to Setsuna regarding Sara in Assiah. When Setsuna freaks out from the turmoil of being in love with Sara, Kira snaps him out of it, saying that his persecutors are smugly dispensing morality from the gallery, not understanding what it's like to be in his shoes - Setsuna's love is clumsy but genuine, so what do it matter if it's in the "wrong"? Kira tells him it can't be helped, and he can't be anyone but himself. It's a really fantastic and compassionate little speech.
SPOILERS!
Who is Kira really? He's the soul of Nanatsusaya, the powerful celestial sword of the Angel Alexiel. Alexiel is cursed to be continually reborn on Earth and suffer a tragic death each time. Through all these reincarnations, Nanatsusaya has taken human form and followed her. He claims this is because he hates her, but it is actually because he loves her. When Setsuna/Alexiel begins his journey into hell to bring back Sara, Kira accompanies him.
Furthermore, Kira/Nanatsusaya's soul is the reincarnated soul of Lucifer, who had fallen in love with Alexiel, rebelled and lost against Heaven, merged his body with the ground of Hell so that his comrades could live there, and lost his memories as his soul inhabited Alexiel's sword. When Kira is killed, Lucifer is revived, changing into a different personality. In the end, he helps Setsuna, showing that even though he appears indifferent, he could not deny his strong relationship to his friend and former love.
Angel Sanctuary
Volumes: 20
Published: Feb 1995 to Feb 2001
Genres: Fantasy, Romance, Shoujo
Author: Yuki, Kaori
Adaptation: 3 Episode Anime OAV
The angel Alexiel loved God, but she rebelled against Heaven when she saw how disgracefully the other angels were behaving. The characters in Heaven were corrupt, their beauty hiding a web of violence, madness, and injustice. She fought on the side of the demons of the underworld. She was eventually captured, and as punishment sent to Earth to live an endless series of tragic lives. She now inhabits the body of Setsuna Mudo, a troubled teen in love with his sister Sara. Setsuna's misery mirrors the chaos among the angels, and their combined passions threaten to destroy both Heaven and Earth. (~ MyAnimeList)
When angels and demons come to awaken Setsuna's power, Sara suffers in the crossfire. Setsuna makes the long journey into the different levels of Hell, and eventually Heaven, getting caught up in the politics and tragedy of the war, all while trying to save his love. Along the way, he'll grow and make a substantial impact on everyone he meets, as well as the world.
Highlights:
- Kaori Yuki's exquisite gothic art style. (I dare say, the prettiest manga ever.)
- Dark and complex storyline that remains interesting as it goes on.
- Interesting themes that push the boundaries of social taboos while, at it's core, being about unconditional love