Azazel's original body, initially, had short, dark hair that covered his left eye. His eyes were green and his skin was notably paler in comparison to how it is after his modifications. He wore a shackled brace around his neck with a chain cut chain attached to the front from where Lucifer had freed him from torture and imprisonment. He often wore dark clothing similar to the one he wears in his modified original form: a cloak with a wide, high-collar in the back.
In Azazel's modified form, he has snowy white hair, similar to Sadow's, and a single, slitted, red eye on his left. The right eye has been replaced by a mechanized one that can follow opponents with a red dot. His uniform in this body is reminiscent to the original's, but red with black lines aligning the sides at some points and a much larger coat collar. Around his neck is a rather strange brace with a code on it, replacing the shackle collar.
Azazel's various other bodies take on Lucifer's characteristics (blonde hair, slitted red eyes).
Azazel is very idealistic and loyal to Lucifer, who he considers a god. He faithfully wishes to free Lucifer and the other trapped Princes of Hell through the use of the Soul Forge, rather than use it for his own purposes. He condemns Demons who try to serve their own interests and explains that every single one of them owes Lucifer their lives and more.
He is rather honourable when he respects his opponents resolve and determination, answering each of Sadow's questions in person before they fight because of his respect for him as well as a parting gift before the man's death. He also admires humanity's refusal to die, fighting to survive even as they near extinction.
He prefers, naturally, to use Lucifer's original body as his means of interaction with others, which may hint that he wishes he were Lucifer himself though Azazel himself explains that he keeps it as his favourite body due to his desire for his lord's return.
He holds a great amount of tact in battle, taking advantage of each of his bodies abilities and using them in conjunction with each other to form devastating combos.