Was it possible for a demon to feel fear?

 Blood dripped slowly from the blade. White hair stained with the red substance.

 Crowley stood frozen, every part of his body completely immobile, fear coursing through his veins. 

 Panic and fear subsided behind the blue irises. Aziraphale's lips parted to speak, but nothing came out.

There the angel stood, weapon in hand, over another angel's dead body. Crowley didn't recognize the angel, but then again he didn't remember many angels from his time in Heaven.

 A wound straight into the chest and through the heart. 

Blood was everywhere.

 Questions raced through Crowley's mind, millions in the matter of those few seconds, but the only thing that came out was a soft whisper of the angel's name.

  "Aziraphale..."

 A pained scream was ripped from Aziraphale's throat and he crumbled to the floor, white wings spreading out before Crowley's eyes. It was only when the angel looked up at the demon, tears brimming in his eyes and called out his name, was Crowley able to move.

 But he was too late. Aziraphale disappeared into a small puddle of sulfur. 

 A small white feather sizzled as it was left behind, Crowley's hand moving out to cup the ashy remnant.

Aziraphale was no more.

~~~

 Crowley bolted upright in his bed, sweat glistening on his forehead. It was that nightmare every single night. The smallest details varied from night to night, yet he was never able to get to Aziraphale in time. For some people, it would be easy to manipulate a dream or nightmare.

     But it was extremely difficult to change a memory.