Author's Notes: Coda to "The Devil You Know". Slight AU for insinuating that Sam and Dean could be pushed far enough to turn on the world.

Summary: Brady understood too late how dangerous Winchesters were together.

Be Afraid

The cockiness Brady had been feeling began to waver as his 'dear uncle' Crowley walked through the last crack in the salt line before vanishing.

His stomach continued to drop as he noticed that the older brother wasn't making a move; well, neither of them were, but Dean held himself back by the salt ring and made no move to draw a weapon. He looked…cold. The kind of calm that settled over a person when they were too furious to function.

But the real kicker was that Sam was standing closest to him, stock still and holding that damn demon killing knife.

Brady attempted to appear unconcerned, but his borrowed human heart was racing. They were just…staring at him. Seeming certain about what the next few minutes held as if it had already happened.

"They just don't get it, do they Sammy?"

"No, they don't Dean."

There was no inflection in their voices, they were stating fact. This was bad. Dean wasn't moving, wasn't poised to move. Every demon knew the older brother was the one that held Sam's leash. But in this case…it looked like Dean had dropped the lead. An uncontrolled Sam was a dangerous, vengeful Sam. This didn't look good for him.

"We're the ones you should be afraid of."

In that moment, Brady understood exactly what that meant. He knew, looking at them now, what these boys were capable of. What they could do, become, if pushed too far. And it looked like that limit was about reached.

As Sam slammed the knife into him viciously, he saw into those hazel eyes.

Brady saw cities crumble while fires scorched the fields bare. He saw blood drenched Winchesters strolling through the center of towns, taking whatever they wanted, and killing anyone who got in their way. He saw carnage and death and madness alight in their eyes.

Brady saw an unstoppable force when the two were together and finally understood why it had been so imperative to keep them separated.

The demon saw the Winchester in a nice shady spot fit for a picnic with fresh blood and bodies, Dean drinking a beer, Sam using the still-warm blood of the dead as finger paint on the grass. He saw Sam rise up and draw fresh red lines onto his brother's face as they both laughed hysterically; the carefree laughter of children that said that all they needed, they had right there beside them.

Brady noticed Dean smirking with pride as his vision dimmed and Sam walked away.

Before the world darkened, all Brady could do was smile bitterly at his new realization. 'They're together now, they're together now…'

And we should all be afraid.