In the opening of S2, we find P1, "Angel of Death" (this is the Islamic understanding of Azreal) the pre-curser of events that happens with Old Knight. Strangely enough, if you do a little examination, and pay attention to the dialogue, one of the things attributed to Azreal, is when the he speaks of the "worthiness" of humanity as a whole. And while in Islam, Azreal is analogous to the "grim reaper" in Judaism, we find a different view, as he is one of the angels sent to destroy the enemies of God, and in one night kills over 70,000. (reaping a harvest of death) He is seen as four faces and four thousand wings, and his whole body consists of eyes and tongues whose number corresponds to the number of the inhabitants of the earth. It can be an interesting study. I think I'll go get a threshing floor... ;)