If you like weird and dark stories that are convulted which make you question the difference between good and evil, coupled with great art, then this is a series for you.
The premise of this series is about a boy(Setsuna) who is a reincarnation of a rebel angel named Alexiel whose crimes against heaven have her reincarnated until the end of time. Each of her lives ends in tragedy until her brother Rosiel is awakened which also in turn drags Setsuna into the middle of things. Confused yet? Just wait, it gets more convulted with political intrigue in Heaven and what is happening in Hell.
The way the story unfolds makes for some interesting characters who are all sympathetic and repulsive in some fashion. Nearly every character has some sort of motivation which will either make him/her hated or loved. So can be said of the side characters.
Setsuna, the main character, is a rather cookie cutter reluctant hero. I found nothing endearing nor did I relate to him. Of course, that could be because of the impossibility of the premise of this series. I found the parts with him as the focus plain boring.
I can also say the same of Setsuna's sister Sara. She was feisty but still couldn't help being the damsel in distress. I will applaud her for being faithful to Setsuna though.
The things that could be taken or left for some readers are the shock-value of the love between Setsuna and Sara who are indeed blood siblings, gender-bending, a bit of a sympathetic Satan, and the fast-paced story which goes from one arc to the next without much of a breather.