Michael

Why is death so frightening?

What fear is there in the unknown? 

Michael didn't know. He knew a lot of things - understood a lot - but this one instinct puzzled him. He certainly never feared death. He thought about it more often than most, yes. He dreamed of it, spoke of it, searched for it. He had seen a thousand people go, and every time there was fear. He had heard a man beg for his life, sobs wracking his body. He had seen the glimmer of uncertainty in the old deacon's fading eyes.
He had watched his own hands choke the hope from a child.
Michael didn't simply wonder about death; he obsessed over it. The reason, of course was simple. He was an Angel of Death. No one had ever told him this, and he wasn't actually certain.
But it would explain the wings.