Survival-Short flash fiction.

It's the little things you notice first.
The blood on his hands had become sticky. The feeling of the hair in his fingers, attached to a chunk of skull with no body in sight. The membranous material hanging from it like a Christmas ornament. The blood, covering your shirt, one sky blue and now deep crimson. The people once called friends.
He couldn't help himself, his mind told him. It had been something he had to do. The survival instinct laid heavy on his shoulders.
What was a zombie to do?