It wasn't that Cas was bleeding. That was a frequent enough occurrence that it didn't even register on Dean's concern meter. Well, not much. When you got shot, you bled. Even angels.

It wasn't even that Cas had gotten shot in the first place. That kind of thing tended to happen. And, Dean figured, Cas could just shrug it off like he always did.

Really, there were two things that were foremost in Dean's mind at the moment. The first was that Cas was not appearing to be able to shrug it off.

The second was that there seemed to be an awful lot of blood, more than a shotgun blast to the chest warranted, and it was getting all over his car.

Yes. It was those two things that dominated Dean's thoughts as he peeled out of the deserted warehouse parking lot, glancing in the rearview mirror every few seconds both to ensure they were not being followed and to add another tick mark to his level of concern as the bright red continued to spread across Cas's shirt like an inkblot. Cas slumped against the back of the seat, half-sitting, eyes glazed as he drew in labored breaths.

Sam was completely twisted in his seat, not having to busy his mind with trivial things like not running off the road, and he had reached back to jiggle Cas's knee. "Stay with us, Cas," he was saying, which seemed useless because Cas was going to be fine.

"You'll be fine," Dean said aloud, as though saying it aloud would firm his conviction.

"Um," Sam said, in a tone that immediately added four more ticks to Dean's concern level. "Should he be…glowing?"

"What?" Dean demanded, taking a chance to twist in his seat and confirm with his own eyes. Yes, every entry wound was incandescent, white-blue through the now-red shirt.

"No." Cas coughed once, weakly, eyes fluttering half-open. "I'm…it's an Angel Blade."

Sam looked perplexed, but Dean added two and two and swore as he turned back to the road. "So Crowley's using Angel Blade brand buckshot now. Great. Dick move."

"So what do we do?" Sam asked Cas, sparing a glance for Dean. "I mean…you're not…"

"Dying?" Cas suggested, managing to somehow sound impatient through the strain. "The notion…has crossed my mind."

"Can't you just heal yourself?" Dean asked.

"There are…" Cas paused, whether in pain or to assess, Dean couldn't tell. "Twenty-seven," Cas continued after a deep, wheezing intake of breath. "No, I can't 'just' heal."

Dean shook his head. "So what? We just —"

"Dean," Sam interjected with the flat tone of urgency. "He stopped breathing."

"Angels don't need to breathe," Dean asserted as he yanked the wheel to the side. Gravel pelted the undercarriage of the car as they fishtailed to a halt on the side of the road. Dean slammed the gear shift into park and launched himself from the driver's seat in one motion, pulling the rear door open hard enough to wrench his shoulder. "Right, Cas? Angels don't need to breathe?"

Cas's mouth was working, jerkily, eyes staring into nothing. Dean swallowed hard against the bile that rose at the back of his throat as he slid into the seat next to Cas.

"Cas. Buddy." He was dimly aware of Sam opening the opposite door, of the hot blood seeping into his jeans as he pulled Cas's torso into his lap. Elevation was supposed to stop bleeding. Everyone knew that.

The light was shining more brightly, now, slender beams that gleamed in Cas's half-lidded eyes. Sharp electric blue pulsed in tiny pinpricks in the angel's pupils. Dean wanted to shake him, slap him, do anything —

"Dean." It was more mouthed than whispered, and if Dean hadn't been so focused on the angel's face he doubted he would have noticed. "I need —"

The pain clouding Cas's eyes lifted for a bare moment as they locked with Dean's, the illumination behind them dimming in its death swirl.

Dean swallowed. Cas was trying to keep speaking, struggling to make his chest rise, but they'd never really needed words for what was important.

He nodded. "Yes. Take it."

Disbelief flitted across Cas's face. Dean screwed his eyes shut and braced himself. "Yes, Cas. Do it."

The sudden radiant incandescence burned through Dean's eyelids, making every spidery blood vessel in them stand out red against orange.

Sam was saying something, something that Dean couldn't hear over the roar that was louder than sound could hold —

And Dean was aware of himself as he'd never been before, of the skin on the backs of his hands and the twists and turns of his veins and the trillions and trillions of cells that formed the galaxy that was him —

Once, hunting a river monster, Dean had been pulled out of the boat into the rushing current of a flood-swollen river. He had tumbled, the cold of the water shocking his limbs into paralysis, unable to tell which way was up. The current had swirled him into an eddy of calm where he drifted for what must have only been a few seconds before he surfaced, sputtering, but for that moment he was suspended in sound and sensation, disoriented and stricken as the current let him go as swiftly as it had taken him.

This wasn't like that, any more than a candle flame was like the sun. But it reminded him of it. Had he lungs, he'd have gasped —

But those weren't his anymore.

This won't take long.

It wasn't speech, exactly; Dean didn't hear the words or remember them being spoken but there they were, floating much as he was in the achingly bright void.

Cas?

Of course.

And then with a jolt, Dean realized that he was not suspended in bright nothingness at all. It was simply a space so large that he couldn't fathom the edges. And suffusing it, thrumming, holding everything that was him together, some intangible force that somehow resonated down to the core of whatever it was that formed him here.

Cas, is this…you?

A…facet, yes.

It's beautiful. He didn't intend to say it, had meant to keep it to himself, but there wasn't precisely a "himself" here. With a slight twinge of what could be panic, it occurred to him how laid bare he was, how exposed, how vulnerable —

Dean. You forget that I've cradled the broken pieces of your soul. Put them back together and placed you back on the earth. Watched you fumble. Fumbled alongside, much of the time. We have always been vulnerable, you and I.

Dean felt a moment of something like vertigo. So I'm just a soul without a body?

You have a body. I've just…temporarily disconnected you from your nervous system so I can use it.

Use it to…?

Heal my vessel.

You said you couldn't.

I couldn't heal myself. The damage the Angel Blade was causing was too catastrophic to heal. But without me in the vessel, it's just ordinary buckshot.

I thought…your vessel was dying. I was giving you a place to go. So that you wouldn't…

I know. An enormous swelling of emotion washed across Dean, one he couldn't quite identify.And I understand what you believed you were sacrificing.

So you're not staying.

I can't. You are far too important to keep locked away in a corner of yourself. And you're not my vessel. Too much time here would cause you damage that even I couldn't repair. I can only be here right now, for this short time, because…

And Dean knew the answer, without either of them saying it. They'd never said it. They probably never would.

It doesn't need to be said.

No, Dean agreed, and the resonance hummed more intensely for a moment, in such a way that Dean could finally place it. It was the satiated euphoria of connection, the intimacy of the first lazy kiss in the afterglow, the undeniable golden thread that wove between the two of them. It was the warmth that burned at the pit of his stomach when Cas was near, that made smiling easier and somehow banished the despair that haunted the edges of Dean's thoughts. It was something he didn't know how to act on, because…

There was no because.

Does it really need action?

It needs something.

Then we'll figure it out as we go. A pause, somehow, though time didn't seem to be passing. It's done. I need to leave.

Will I remember any of this? Since you unplugged me?

Some of it. Memories of emotions, maybe, but not words. A feeling of amusement threaded through the essence that surrounded Dean. Or did you think we've been using words this whole time?

Another tumble, a massive lurch that was not at all like falling but much more like being very suddenly lifted to a great height, images and light and sound and sensation rushing and demanding, the cloth of his shirt the weight of a mountain on his shoulders and his lungs burning, expanding with his gasp as he landed very firmly back in himself.

"Dean?"

Dean blinked, eyes aching as they brought the world into focus. He was still sitting in the backseat of the car, Cas's torso still in his lap. The blood was still warm. But Cas's chest was rising and falling, slowly, without the obvious labor it had required before, and serenity had smoothed the wrinkles of his face into calmness. He just looked tired, now, and didn't react as Dean lightly ran his thumb over the stubbled jawline.

Sam's hand on his shoulder, shaking it, made Dean look up. "Dean! What the hell happened?"

Dean let his gaze drop again, not sure he could meet his brother's eyes. "I don't know," he answered, not exactly honestly — something had transpired, something that was rapidly losing definition and receding in his mind like a dream, leaving nothing but vague impressions and a seed of blissful content deep in his chest.

On an impulse, he leaned down, pressing his lips against Cas's forehead for the briefest of moments before straightening and propping the limp, sleeping angel against the back of the seat in a sitting position. He ignored the soft sound of astonishment Sam made. "We gotta go. They could still be tailing us."

He felt…strange. Not awake. But not fatigued. Everything was just a shade too bright, too sharp, and yet none of it seemed to penetrate the haze that hung in Dean's mind like gossamer. Dean shook his head as he closed the driver's side door and shifted the car into gear. Sam slipped into the passenger seat next to him, his eyes questioning.

"How long was I…out?" Dean asked as he waited for a beat-up burgundy minivan to pass them.

Sam shrugged. "Ten seconds? Cas jumped in, healed…himself…and then went back."

"Ten seconds? No, that had to be…" Dean trailed off, peering in the rearview mirror to confirm that the lane was empty, and found himself staring into the middle distance, not seeing anything. Taking a deep, shaky breath, he blinked hard, running his hands over his face.

"What happened in there?" Sam asked slowly.

The idling engine gave a dull roar, as if impatient. Dean glanced in the rearview mirror again.

The mirror had been knocked askew, probably in his previous haste to get to the backseat; as he reached up to fix it he caught the briefest reflection of Cas. Almost, it seemed as though something much larger occupied the body, something seen from the corner of the eye that disappeared when Dean turned to look more closely.

Cas's eyelids fluttered, and the tiniest of smiles played at the corner of his mouth.