Notes: This story was inspired by / shamelessly stolen from an episode I love of one of my other favorite TV shows. I'm 509% sure people will figure it out at some point, but just in case, I'll admit it at the end. :)

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Within Me

Something about you that makes me feel bad
I wasn't there when a thin line destroyed your soul

I search every corner there's nowhere to hide how I feel
Ignorance, sacrifice
Some days it's harder

Now I'm aware when a man falls
Rebound, my fault
lacuna coil x within me

Dean would relive the beginning of the hunt over and over again throughout the next few months. There were so many things he would regret not thinking of, but by the time everything happened, it was way too late for anything but sorrow.

Cas had been human for a few weeks now, ever since the grace had turned out to be the last bit of the spell needed to de-Mark-ify Dean's arm. He'd started talking about hunting after just a couple weeks, eager to dive into the human world of his own volition this time around. Despite the brothers' hesitation and uncertainty, Cas had worn them down, and they'd agreed to let him come along on a routine ghost hunt.

"I wanna go after the ghost," Cas had said, endearingly gung-ho as he packed a bag with iron, salt, and spare lighters.

And Sam and Dean had agreed, throwing in a shotgun to round things out.

That was their second mistake. Bad enough to bring in someone new, someone vulnerable because he was human and used to having heavenly powers at his disposal. Bad enough—despite the training he'd undergone in the few weeks beforehand. And a whole lot worse to bring him into the thicker of things on trial run #1. Sure, maybe he'd have been pissy to merely be doing grave-digging work, but better pissy than d—than—

But ghosts were a dime a dozen and easily enough dispatched, Dean remembered thinking.

Fucking idiot.

xxxxx

He leans in. Crosses his arms on the edge of the bed and drops his head down, one watery eye stinging with the miniscule pain of a loose lash edging free inside the lid. He doesn't bother wiping his eyes anymore. The area beneath them is rubbed almost raw.

"Dean—"

"Shut the hell up, Sam," Dean growls, and scoots his chair closer to the silent bed.

xxxxx

If only they'd read the reports of the damage more closely. They might have realized there were actually two ghosts. Twins. Oddly enough. There wasn't one victim out for revenge, there were two.

So as Sam went into the graveyard to salt and burn the bones, Cas and Dean had traipsed through the house, trying to lure out what they thought was one ghost. They'd separated. Cas to the basement, Dean upstairs.

The younger twin's ghost showed up in the bathroom on the second floor, but she hurled the lid of the toilet tank at Dean's chest with more strength than he'd have thought possible, slamming him back against the wall. Ended up hitting his head so hard that he'd needed a second to get his bearings back. At that moment, a sickeningly loud bam echoed all the way up to the second floor.

Dean had been fighting the younger ghost, barely managing to dodge more projectiles before swinging a wrench through the damn thing. All the while, Cas was losing consciousness, lying in a pool of blood at the base of the pipe he'd been knocked head-on into. Dying. Alone.

xxxxx

"We're gonna have to get him out of here—" Sam's voice is barely sewn together, Scotch tape and Velcro, emotions poking at the holes still gaping. "B-burn his b—…"

"You say another word, I'll burn you," Dean utters, reaching one hand higher up on the hospital bed to twist into cold fingers.

He's bodily pulled away by an orderly after four hours.

xxxxx

xxxxx

It's your fault. It's your fault. It's your fault.

They stand in the clearing, cool early-summer air yielding to the warmth of the fire surrounding Cas's body. Dean stares blankly, barely able to pay attention to anything beyond the regular drum beat of blame pounding through his mind.

Your fault. Your fault. You left him alone.

Sam takes a half-step closer and rests one hand on Dean's upper arm. Shifts his weight slightly. Out of the corner of his eye Dean can see him open his mouth and then close it again.

What is there to say?

Sam settles for squeezing Dean's arm instead, trying to support his brother without words.

You did this, Dean. You did this. YOU.

The fire crackles suddenly hard, as if agreeing.

You.