Author's Note: Spoilers for "Road Trip". I hope you enjoy this piece!

"And I'd fight for you

I'd lie, it's true

Give my life for you

You know I'd always come for you."

—Nickelback, "I'd Come For You"

The Impala's taillights are nothing more than a distant red speck on the road that seems to stretch endlessly out into the horizon. The night is eerily silent, save for the rumble of a few car engines, and the cold is biting and sharp. A cloud passes over the yellow moon, blocking what little natural light exists.

To say that the night has yielded nothing but trouble is an understatement.

Sam stands in front of him, shivering. His gaze is devoid of any hint of warmth, any trace of emotion. Grimacing in pain, he watches his older brother finally disappear out of sight. How he's still standing—grace or no grace—remains to be seen. The damage he's suffered—both because of the aftereffects of the trials as well as Gadreel's hasty exit—is extensive to say the least. He should be in a hospital, hooked up to a thousand different monitors and getting a healthy dose of oxygen. Instead, he's here, watching his brother fade from view.

"Shit." Sam swears finally, voice barely above a whisper. He runs a hand through his hair, sighing. His body begins to list and immediately, the angel moves to support his friend's body. Sam's skin is clammy to the touch and his heart beats out of rhythm.

"Sam?" Castiel asks, though he falters. What's happened tonight with Dean, what's been happening in Sam's own body—the angel doesn't know where to begin. All he can do now is stay by the youngest brother's side and hope that his presence will help stop the pain somehow.

"He's gone." Sam mutters. "He actually left." He barks out a laugh, bitter. "He's never . . . we've never . . ." His voice fades and his wide-eyed gaze comes to rest on the angel's face. "I killed Kevin, Cas."

And the heart within his vessel breaks for this man—no, this broken boy—that's barely holding himself upright in front of him. Castiel wants nothing more than to shelter him from the world and patch him back up again.

"Sam, you didn't—" He protests, only for Sam to hold his hand up for silence.

"Just . . ." The man's voice before him is strangled, rough and laced with such an acute pain that it actually hurts to hear him speak. "Don't, Cas." He rubs absently at his chest, at where his tattoo used to be and the angel nearly sighs in relief because healing the physical pain is something well within his power. It's something he knows how to do with skill.

"We must return to the bunker." He tries to summon a commanding tone, something that will spur Sam into wanting to take care of himself. But seeing the grief in Sam's eyes, his own voice falters, grows pleading, "You need to rest, Sam."

For the longest time, there is silence.

"I need to get some air." He finally says, barely above a whisper.

"We are outside—" The angel begins.

"Five minutes." Sam sighs raggedly. "Just once around the block." He gestures vaguely to the road, to the sidewalk that lies alongside it.

"You need medical attention—" Castiel protests, because the idea of Sam facing this alone, of being alone in this troubling time, terrifies him. He's failed the youngest Winchester before—the broken wall fiasco springs to his mind—but he refuses to fail now. He will take care of Sam; he will keep him safe.

He won't let Sam down now, not when he needs Castiel the most.

"Five minutes." Sam repeats, an unspoken plea evident in his tone.

The majority of the angel wants to argue, to drag Sam to the car and drive as fast as they can back to the bunker where Castiel can protect him from the cruel forces of Heaven, Hell and all manner in-between.

But . . . it's clear that Sam needs this time, to clear his head, to process all the information that's been hurled at him.

"Five minutes." Castiel acquiesces, forcing himself to stay rooted to that one spot as Sam begins to move to the sidewalk, begins to become a speck in the darkness. Once the youngest Winchester is out of view, he curses under his breath, like Dean does.

"Four minutes and counting." The angel sighs.

But for Sam, he will wait as long as it takes.

He's not going anywhere.

Sam's hands are shaky on the wheel.

They've only been driving for ten minutes but it's obvious that the youngest Winchester is having a hard time focusing on the task at hand. Every few minutes, he lifts a hand from the wheel and pinches the bridge of his nose, seeking relief from whatever pain plagues him.

"Migraine?" Castiel ventures and Sam nods.

"Feels like someone is digging into my skull." He practically hisses, once again trying to get rid of the ache. "Fuck."

"I apologize." The angel murmurs. "I can only heal you in stages—"

Sam waves off his concerns.

"It's fine."

Silence.

None of this is really fine though. Kevin's dead, Dean's gone and Sam's functioning on the heavenly equivalent of a patch job and they're still 30 minutes away from the bunker. The angel frowns.

Dean would know what to say to get Sam to give up the wheel and allow someone else to drive. Dean would know how to get his brother to stop feeling guilty for a death that he had nothing to do with. If Dean were here—

But Dean isn't here; Castiel is and that will have to do.

"Sam."

"What?" The tone burns, frustration practically dripping from the word.

"Let me drive."

"Drive?" Sam echoes, dumbstruck. "Cas, you don't know how to—"

"Dean's taught me, should the need arise." They run a stop sign and the minivan trying to cross the intersection honks at them in reply. "Sam, pull over."

"I can do this."

Castiel spares himself from another argument and reaches for the wheel.

"Cas, stop—"

The car comes to rest on the shoulder.

"Sam, you need rest." He unbuckles his seatbelt. "Let me drive." Then, even softer, "Please."

"Fine." Sam grumbles, unbuckling and opening the driver's door. Castiel mirrors him and within seconds, they're back on the road once more. "Since when have you known how to drive?"

"Since the Apocalypse." The angel confesses. "Dean thought it best to learn just in case I was unable to teleport to you two." He smiles brightly. "It seems to have come in handy now."

"Yeah." Sam's eyes begin to droop and he forces them back open.

"I'll be okay should you wish to rest."

"Cas . . ." He waits to hear a reply, but Sam shakes his head instead. "Just . . . thank you."

"You do not have to thank me for my assistance, Sam." The angel replies softly. "You are my friend and as such, I'm glad to help you."

He glances over to look at the youngest Winchester to add something else, but Sam is already asleep. Castiel smiles softly, pleased that Sam is finally getting some rest.

They'd be at the bunker soon and Castiel could begin to piece Sam back together again. Once Sam's health was no longer a concern, he'd try to help the two brothers reconcile. It wouldn't be easy—both were stubborn and both had valid points—but they needed each other. But first, he'd take care of the youngest Winchester.

"Rest well, Sam."

One battle at a time, after all.

Once they reach the bunker, Sam sleeps soundly.

His rest is untroubled, free of any nightmares. It seems that for once, the youngest Winchester's mind is blissfully blank, allowing his body to take its much-needed time to recuperate. It's odd really, to see the often-troubled man before him actually sleeping peacefully. Odd, but Castiel is grateful for this small miracle. Sam's body is broken, barely functioning, and he would require as much rest as he could get.

Dean still hasn't called and Castiel's own message has gone unreturned. He doesn't know what exactly is running through the elder Winchester's head, but if there is one thing the angel has learned, it's that Winchesters are stubborn and they could hold a grudge for what seemed like an eternity. Until Dean is ready to deal with the situation at hand, the angel can expect more unreturned calls.

Which, for right now, is okay. Sam is sleeping and Castiel has the watch. Nothing will happen to the youngest Winchester now, not while he is here standing guard. For once, they'd caught a break.

He rises from the chair in the corner of the room and leaves Sam to his rest. He's only been at the bunker a few times and he wants to make sure all the sigils are correct and up to date. The boys have added angel proofing, but perhaps Castiel can add a few more just to be safe.

He moves quickly through the bunker, scanning the area for any sigils that need to be improved upon. He checks each room thoroughly, making sure that any doors leading to the outside are firmly secured. This is how he stumbles upon it—

Kevin's room.

He knows, logically, of course that Kevin has died. He understands what happened, knows exactly how the young prophet hadn't stood a chance, but seeing the bedroom now fills the angel with a grief he didn't know he harbored.

The bed is unmade, sheets rumpled, like someone just got out of it and would return to it soon. The walls are bare, but the bookshelf is filled with various comic books, technology guides and a few DVD's strewn in. On the desk, a framed picture of Mrs. Tran and Kevin beams at him next to an open Bible. He leans in and sees the page Kevin had been reading about contained a bit of information on prophets. On the bedside table, there is a note from Dean, informing the prophet to "stop being a fucking hermit and come eat some dinner with us". It brings a small smile to the angel's lips—this is Dean's way of showing that he cares after all.

But Kevin won't be coming back to eat dinner.

Kevin is dead.

This is all he left behind; all the world would ever know about Kevin Tran is contained in this room. No one would know about the sacrifices he made, living a life he never wanted. No one would understand what he lost along the way or how he suffered. Soon, even the memories will fade and those who knew him would wonder years later who exactly that boy had been in their high school classes, the AP student who'd been on his way to a prestigious school and a life full of success. They'd struggle for a name to put to the fuzzy image in their mind, until they'd finally shrug and give up, thinking it no longer important. Thus, Kevin Tran would die once more.

But Castiel will remember and that will have to do.

He closes the door behind him, sealing away the sadness for the moment.

"Hey, Cas." Sam greets him the next morning, voice hoarse and dry. He rubs his eyes and practically collapses into the dining room chair.

"Good morning, Sam." The angel greets, frowning somewhat. "How are you feeling?"

"Like crap." The Winchester replies, pinching the bridge of his nose. "My head won't stop pounding."

"Perhaps, I can help with—" But as he comes to stand next to Sam, the younger brother flinches. "Sam?"

"Sorry." Sam flashes him a bright grin as he stands up from the chair. "I'm just a bit jumpy . . . you know, angels and stuff."

"Of course." Cas nods, but he doesn't believe the words coming out of Sam's mouth. Though he could understand Sam's hesitance over accepting an angel's help, he should know Castiel better than that. He treasures Sam's friendship and though he's committed a few grievous errors in judgment when it came to the youngest Winchester, he would risk doing so now.

"I just need some air." Sam mutters, moving towards the hallway.

"Sam, wait—"

But the footsteps echo in the hallway and then a door slams shut.

Leaving Castiel to wonder just what exactly has happened.

Hours pass with no word from Sam.

Knocks on his door go unanswered as well as various meals that the angel prepares—quite well, actually, during his time as a human he did excel at cooking—leaving Castiel to wonder what exactly he should do. Sam would need his next treatment soon or his body would begin to shut down, the damage from Gadreel and the trials still too much for his own body to heal on its own. He doesn't understand why Sam is doing this—perhaps the stress of the past few days, perhaps the misplaced guilt of Kevin's death—but regardless of the reason, he has to get through to Sam.

"Sam." He knocks on the door once more, insistent. "Sam, you need your next treatment."

There's no reply. He tries to turn the knob, but it's locked.

"Sam, please."

Still nothing.

"Fine. I shall not be held responsible for my next actions then." He takes a step back, and then charges into it, bursting it open. "Sam?"

The youngest Winchester rises from his bed, a malicious grin spreading on his lips.

"Now, Castiel, really." His voice chides, singsong and dripping with venom. "Didn't anyone ever teach you not to break things that aren't yours?"

Dread settles in the pit of his vessel's stomach and he immediately knows that something is terribly wrong. This isn't Sam that stands before him. How could he not see the signs earlier?

"Who are you?" Castiel hisses, summoning the full power of his grace. Instantly, the heavenly light fills the room, illuminating every crevice and banishing the darkness. The thing in Sam shrinks back in pain, but its coal black eyes immediately glare at the angel's.

"Surely now, you recognize the Queen of Hell."

"Abaddon." The grace consumes him now. He can feel it entering every part of his vessel's body, feel it embracing him as comforting as a mother's warm arms. "You will perish—"

"Now, now," Abaddon murmurs, a smirk on twisting Sam's visage into a grotesque parody of what his smile normally looks like. "You drive me out and you'll kill Sam."

That gives him a moment's pause.

"I'm the only thing keeping precious Sammy alive, you understand?" Abaddon shouts, over the din of the grace swirling around in the room. "I know what he's been through, I've seen his memories! Do you think he can survive two exorcisms in his already fragile condition?"

And though it pains him to admit, Abaddon is right. Sam was barely on his feet after Gadreel and he hadn't had enough treatments in order to repair the previous damage. Getting rid of the demon would be the straw that broke the camel's back. Sam would never survive it.

It's a stalemate.

He lets go of his direct connection to Heaven. The warmth and grace leaves him and his cerulean eyes meet the inky dark ones that currently occupy his friend's face.

"When?" He growls and she chuckles, darkly.

"I've had eyes on those two boys forever. When I heard Sam's damn anti-possession tattoo was gone, it was almost too easy." She brushes past him, leaning in to his ear, voice barely above a whisper. "Sometimes, all you need is five minutes."

Castiel grips her arm and she laughs, loud and boisterous.

"Careful there, angel." She narrows her gaze. "Wouldn't want you to damage this fine packaging any more."

"I will not allow you to possess Sam." He snaps. "Release him!"

"You are not in a position to be giving me orders!" She retorts. "I can kill Sam at any moment, you understand me?" She uncurls his hand from Sam's arm. Then smirking, she adds, "Face it, angel. You've lost. Big time."

That's when she knocks him out.

Author's Note: The final part is already written and will be up very soon! Let me know what you guys think if you have a moment. Thanks!