Author's Note: So, this wasn't supposed to happen, lol. From my senior year of high school through the first half of college I was fairly established in the world of fanfiction. About a year and a half to two years ago, as I began to wrap up the last of my in-progress stories and look toward starting a sequel that I had promised, I decided that said sequel would be my way of bowing out from the world of writing fanfiction in favor of focusing on my original ideas, which I feel like I now have the skills and wherewithal to tackle. Then, a few weeks ago, I decided, on a whim, to read a bit of Supernatural fanfiction, though I haven't regularly read fanfiction for years. I have a habit of playing out scenes in my head (with my own characters or someone else's) as I fall asleep, to give my brain something to occupy it that fades more naturally into sleep than "OMG, remember all the things you have to do/could have done better?" Naturally, Dean & Cas and Sam & Gabe took up residence for a few nights after I started reading Supernatural fanfiction. Nine times out of ten, these scenes get no farther than the moment I doze off. The tenth time they become a major plot bunny leading to an idea for an extended fanfiction I never intended to write but about which my brain will now literally not shut up. Oops. But you're here to read my story, not about my story, so I'll let you get on with it after a couple pertinent notes:

One: This is the first story for which I have a beta. Well, actually I have two: one because I offered to let her read the chapters before I post them, the other because I decided I needed a Sap Police. The Supernatural characters are a lot older and, for lack of a better word, more macho, than the characters I have written in the past. I can get away with having Al & Scor, Kurt & Blaine, even Artemis & Holly do and say things that would be beyond laughable coming from Dean & Cas or even Sam & Gabe. So I asked my friend, a guy in his late 20s who is a huge Supernatural fan (model of the Impala, Samulet, Dean jacket, selfies in front of the Men of Letters Bunker exterior), but doesn't read fanfiction or ship Destiel (he's not against it either. Please don't start a war. That's like the only thing that this fandom fights over & I think it's ridiculous, as both sides obviously have validity. PM me if you want my full analysis on that), to read my chapters before I post them, mostly for characterization/character interaction believability. If I can convince him, then I've accomplished something.

Two: It was unbelievably difficult to find a point in time once Jimmy is happily in Heaven (because the poor guy really doesn't need to be privy to Cas & Dean's eventual romance. Ew) where everyone involved is themselves. No soulless Sam, no Mark of Cain, no Human Cas, no no spells, no brainwashing, no trying to become God (seriously Cas, get your shit together, lol). I made a SPN chronology jus to sort everything out. In the end, I did have to erase Rowena's attack dog spell from the end of Season 10/beginning of Season 11 in order to set my story there and have events work as they need to. Considering how much I dislike Rowena, it didn't seem like much of a sacrifice. Don't get me wrong, Ruth Connel is the shit. Her SEACon panel almost made me forget how annoying I find her character. And actually, I found her more palatable in the last few episodes of Season 11, but that's beside the point. Which is: This fic starts at the end of Season 10/beginning of Season 11. Everything is pretty much canon up to then except for some character interactions and no attack dog spell. The prologue is mostly retellings of and additions to parts of the second half of Season 10, to set things up. Obviously events in Season 11 will change, but I am hoping to weave the general plot of Season 11 through my story.

Now, on with the show!

-SQ

Disclaimer: Does Snakequeen-in-Norway look like a pen name Chuck would use to you?

Prologue

Dean could have blamed it on the Mark of Cain, but he knew that alone didn't justify his actions, not really. The hunter glared down at his clasped hands, his exposed forearm now unblemished save for the usual scars inherent to his line of work.

The arguments had started out small.

"Dude, Claire's sending you a pretty clear 'screw off' message, maybe you should listen to her. I mean, you look like her dead dad; can you really blame her for not wanting you around?"

Castiel gave Dean a glare that was as much human as it was Angel of the Lord. "She is still a child, Dean. She needs someone in her life who cares for her."

"Believe me man, I get it, I'm an expert on the whole guilt thing, but I think you should take a back seat on this one."

"Don't tell me what to do, Dean."

"Cas, you're not her father—" but the angel was already gone.

Dean didn't know when they had stopped making up after each fight. Probably the same time he lost count of how many there had been.

"Dean, I do not think it advisable for you to hunting this condition."

"I'm fine," grunted Dean, wrapping a bandage tightly around the cut on his arm. "It's barely a scratch; I've had worse."

"While it is rather more than a scratch, I was not referring merely to your physical wound."

"You think I'm going crazy?" said Dean "Is that what you and Sam have been whispering about? Don't think I haven't seen you, gossiping like school girls."

"Dean."

"Do you think I'm too delicate to hear what you two have to say about me, is that it? Because you spend so much of the time you are around with Sam these days, I'm surprised you two haven't tied the knot already. Why don't you guy him a ring and be done with it?"

"Dean."

"I'm still here you know, I haven't died yet. And I'm still me—I'm not just this thing on my arm." Dean gestured angrily to the mark of Cain.

"Dean!" Dean felt his jaw shut seemingly of its own accord and glared daggers at the angel in front of him. "Dean," said Castiel in a softer voice. "I am merely concerned for you. Sam and I both are."

"Yeah, well, don't be," said Dean, massaging his jaw. "And don't do that," he added. You'll waste your Grace."

*****SPN*****

"Dean, we need to talk."

Dean didn't look up from the gun he was cleaning. "No, we don't."

"Dean, I would very much like to talk to you."

"If you can't tell, Cas, I'm a little busy right now."

A sigh. "You always seem to be busy lately, Dean."

"The pot calling to kettle black, are we?"

"I do not see any cook ware here, Dean."

Dean took a deep breath, clenching his fists to keep the irrational rage in check. "Just. Get. Lost. Cas."

*****SPN*****

And the dreams, the visions—they didn't always come only when he was asleep—didn't help matters either.

His fist made a satisfying sound as it collided with Castiel's ribs again and again, drawing a strangled grunt from the angel as the bone splintered beneath the skin. Dean grinned and aimed a punch at Cas' jaw, feeling the warm blood blossom over the pale flesh, staining his knuckles crimson…

Dean sat up in bed with a jolt, heart racing, the Mark of Cain burning on his arm. He drew a shuddery breath. It hadn't been real. This time. But Dean knew he wouldn't sleep any more tonight.

There were times, waking, otherwise lucid times, when he wanted to hurt Sam and Cas, could almost feel the thrilling sensation of their flesh ripping beneath his hands. And as the idiot angel still didn't seem to understand the concept of personal space, sometimes Dean's only choice was to up and walk away. Rude, yes, but definitely better than the alternative.

Well, maybe if Cas was mad at Dean, he at least wouldn't hesitate to kill him when the time came.

*****SPN*****

Dean surveyed the carnage around him with a sense of satisfaction. He had ended those sons of bitches, and it had felt good. Pleas for mercy had no effect on Dean Winchester—the Stynes were monsters, and monsters got what they deserved.

"Dean."

Dean turned around slowly. The blood was pounding in his ears so hard that it was difficult to hear the angel's words, but his eyes were hard as they met Castiel's.

"What have you done?"

The answer being obvious, Dead didn't bother to respond. He observed with a detached distain as the once aloof celestial being bent over the bodies as though they meant something other than three fewer monsters polluting the Earth.

"You killed him," said Castiel, with his inherent knack for stating the obvious. Dean resisted the urge to role his eyes with difficulty.

"I took down a monster. Because that's what I do." Dean spoke slowly and carefully, as though using each word to anchor himself to reality. "And I'll continue to do that, until—"

"Until you become the monster." Cas was facing Dean again, the expression on his face a combination of heartbreak and accusation.

Dean, for once, held his gaze, turning around only once he had dismissed the bleeding-heart angel. "You can leave now, Cas."

Perhaps using the angel's nickname had been a mistake; it seemed to bolster Castiel's resolve.

"No," he said, and Dean could have laughed at the way Castiel still thought he had any right to issue orders to Dean. Or to anyone.

"I can't," continued Cas, advancing on Dean's retreating back. "Because I'm your friend."

Something stirred in Dean then, something soft and weak and far more dangerous than the Mark of Cain. But the same word that had given life to the feeling also provided him with the means of extinguishing it.

When he had a handle on his emotions, Dean turned around and sized up the man-shaped angel facing him across the body-strewn room. A different fire burned in his mind now, one of hatred and rage. He advanced on Castiel, his eyes blazing.

"Let me ask you something," he threw the accusation at the angel like a curse. "You screw over all your friends?"

"Sam and I were trying to cure you. We still are."

The two were almost nose to nose now; Dean could feel the air he knew Castiel didn't have to breathe on his face.

"Like hell."

Cas was fumbling now for words, Dean could see it.

"We can read the book now." And apparently also for ideas.

"Yeah, so what? So you might find a spell that might take this crap off my arm?"

Vaguely Dean registered the desperation in Cas' expression that would have once made him drop everything to bring a smile to that face again. Now it just made him angry.

"Well, even if you do, what's it gonna cost?" he challenged. Fucking naïve bastard, always had been. "'Cause magic like that does not come free. No, it comes with a price that you pay in blood." And no one, not Cas, not Sam, not even Crowley was going to pay that price for him again. "So thanks, but no thanks. I'm good."

It took more effort than it should have for Dean to break eye contact and turn away, but when he did, Cas put a hand on his shoulder, pulling him back.

"No," he said again. What an infuriating word, 'no.'

The stupid son of a bitch turned Dean to face him again—seriously, did he have a death wish?—and when he spoke, the mixture of pity and contempt in his voice was sickening. "You're not. Maybe you could fight the Mark for years, maybe centuries like Cain did, but you cannot fight it forever. And when you finally turn, and you will turn, Sam, and everyone you know, everyone you love, they could be long dead. Everyone except me. I'm the one who will have to watch you murder the world, so if there's even a small chance that we can save you, I won't let you walk out of this room."

Halfway through Cas' fucking Oscar speech, Dean found that he could no longer look at the angel, but his voice was steady as he uttered his contemptuous reply. "Oh, you think you have a choice?" The second half of the question: You think any of us have a choice? went unspoken.

"I think the Mark is changing you."

Dean had to give Cas props for courage at least.

"You're wrong." Or if he wasn't, it didn't matter.

"Am I? Because the Dean Winchester I know, would never have murdered that kid."

"Yeah, well, that Dean's always been kind of a dick."

Again, Castiel stopped him, as if he could possibly deny that statement. Damn angel didn't know how to quit while he was ahead.

"Dean, I don't want to hurt you."

Cas' earnestness, his goddamned laughable amount of faith after all the shit that had gone down between them, and that other emotion, the one Dean would not, could not name, very nearly broke Dean. So he did the only thing he could: He broke Cas first.

It was just like his darkest fantasies, only a hundred times more real. The feeling of Castiel's skin breaking against his knuckles, his joints screaming as Dean bent them in ways no human body was intended to bend. The spurt of the warm, red blood across his hand. Dean pulled away with difficulty, unwilling to let this play out to its inevitable conclusion.

"Dean. Stop."

And still, even after everything, against all his better judgement screaming at him to go, Dean had no power to resist that voice.

His fist collided with Castiel's jaw, and this time the punch wasn't pulled. Again and again he rained down blows on his former ally, the man he had once referred to as family, a thrill going up his spine at the satisfying thunk the other man's head made each time it hit the table. Dean saw red. Castiel was going to die and he, Dean, was going to love every second of it. Dean found Cas' Angel Blade and ripped it from his sleeve, holding the weapon poised above the helpless and bleeding angel, just like in his dreams.

With an effort, Cas forced his eyes open and lifted his hand, clasping the wrist of the hand Dean had fastened around his tie and the front of his shirt. "Dean," he said, the utterance more of a grunt than a word. "Please…"

Dean's entire body shook with the desire, the need to plunge that blade into the angel's heart. But his eyes…he couldn't tear them away from Cas' piercing blue ones. The seconds dragged on indeterminably as they stared at each other, assailant and victim, human and angel. Cas' life was literally in his hands, and they both knew it.

Dean brought the blade down with a sickening rending sound. Castiel turned his head to look at the weapon, embedded, still quivering, in the stack of books beside him.

"You and Sam stay the hell away from me," said Dean, stalking out of the room, his tense shoulders like a physical barricade between himself and anything foolish enough to try and touch him. "Next time I won't miss."

Castiel watched him go, his breathing ragged through quickly swelling lips, and for the first time since he had gripped him and raised him from perdition, he believed that Dean Winchester could, and would, kill him.

*****SPN*****

Dean shook his head angrily. The son of a bitch was gone; Dean had seen to that. He had had enough of the angel coming and going like a damn yo-yo and had told him as much when he had called after the Mark had been removed and something worse than Hell broke loose.

"Where the hell are you, Cas?" Dean snapped into his phone, not at all in the mood for pleasantries.

"I'm okay," came Cas' voice from the other end of the line, not sounding very okay. Damn angel never gave a straight answer; why would now be any different?

"Dammit, Cas, where are you?"

"Just please tell Sam, Rowena escaped with the Book of the Damned and the Codex," continued Cas, as though Dead hadn't spoken.

"I'm not your messenger boy, Cas," said Dean angrily. "Next time you want to talk to Sam, you call his phone."

"Dean—"

"No, Cas, I'm sick of this. I'm sick of your cryptic-ass angel talk, I'm sick of your manipulation and your deceit, I'm sick of you going behind my back with Crowley, and with Rowena. With my own brother! And I am so fuckin' sick of your damned disappearing acts. So you tell me where you are, or so help me—"

"Dean!" The word was like a slap. "The Mark. Is it gone?"

"Yes," snapped Dean. "It's gone. Whoopie. Congratulations. You happy?"

"No," came the angel's voice finally, the tone tight and clipped. "I am far from happy. I have killed for you, lied for you, risked my life for you, literally died for you. I fell for you, choosing your sorry ass over the entirety of Heaven, and you think I am going to come and go at your beck and call like a goddamn guard dog? No, Dean, I am not fucking happy."

The tension was so thick that Sam could feel it. The baby fussed in Jenna's arms and the girl bent to quiet her.

"Cas," said Sam loudly, breaking the silence. "What can you tell us about the Darkness?"

Now Cas' voice was confused. "Why would I tell you about the Darkness?"

"Because it's free," said Sam, taking the phone from Dean and putting Cas on speaker.

Another long silence, then, "No, that can't be."

"Yes, because you saying it can't be makes everything all hunky-dory again."

"Dean, enough! Removing the Mark opened some kind of lock," Sam continued into the phone. "Dean saw her."

"The Darkness is a woman?" said Cas, an undecipherable emotion creeping into his already many layered voice.

"That's what we're asking you," said Sam. "We don't know what she—or it—is. We were hoping you might know more."

"We don't need his help," snapped Dean, grabbing the phone back from his brother. "If he even knows anything useful, and is willing to tell us, both of which I doubt."

"Dean, knock it off!"

But Castiel wasn't paying attention to the brothers' scuffle over the cellphone. Something had moved in the trees behind him and as he turned his head, his eye caught the glint of moonlight off an Angel Blade.

"Sam, Dean," he cut in, his voice urgent enough to cause the Winchesters to pause. "Goodbye. It may be some time before we see one another again."

As he went to disconnect the call, he heard Dean's voice slice across the distance between them like a knife. "Make that forever, Cas." Then the line went dead and Cas turned around to face the two angels behind him, both of whom were looking at Castiel as though Christmas dinner had come early, and he was the main course.

*****SPN*****

Dean hadn't heard from Cas since then. Not that he had expected to, he told himself. He had made it clear that he didn't want to see that angel again, and he stood by that. It was better this way. He knew Sam had tried praying to Castiel a couple times, with no result, but Dean hadn't, and he had no intention of doing so. Or of admitting that part of the reason for that was that he was afraid that Cas' wouldn't respond to him either.

Dean shuffled down the hall to the bathroom to take a piss, the real reason he had woken up anyway, and then climbed back into his bed, resolutely, and somewhat forcefully, shutting off the light.

*****SPN*****

"Thank you,"

"Don't thank me yet."

Hannah unchained Castiel's wrists and brought him a chair, which he sank into gratefully.

"I'm not lying about Metatron."

Hannah nodded. "I know. Can you tell me anything about the disturbance in Superior Nebraska?"

"You know about that?"

"Alarms have been sounding in Heaven, Castiel. Alarms that haven't gone off in…ever. We don't even know what they mean."

Castiel couldn't meet Hannah's eyes. "Those alarms are for the Darkness," he said, feeling a stab of guilt at the expression of shocked confusion that appeared on Hannah's face.

"The Darkness is a story."

"No," Cas seemed to be saying that a lot lately, "it's not."

Hannah listened to the rest of Castiel's explanation in mounting horror. "God help us."

If the situation hadn't been so dire, Castiel could have laughed. "I wouldn't count on that."

Hannah seemed to have come to some kind of decision. "Where is it?"

"I don't know," said Cas honestly.

"Then who would?" demanded Hannah. "The Winchesters?" she continued. "Castiel, if this is true, then it's the end, for all of us. Sam. And Dean." Cas couldn't tell whether or not he was imagining the slight stress Hannah put on Dean's name. "Where are they?"

"I don't know," said Cas, only half a lie.

"Then think harder!"

Cas narrowed his eyes. "How did you find me?" he asked slowly.

"I saved you," said Hannah, after a beat of silence, but his hesitation was all the answer Castiel needed.

"No, I don't think you did," he said, the pieces of the puzzle coming together in his head. "I think that you told Ephram and Jonah to bring me here, and to hurt me, and so you arranged to burst in and save me." Castiel gave the angel he had considered his friend a look of utter contempt. "You were hoping that I would be so grateful that I would do anything. You said that I would tell you anything that you wanted to know." Grief stabbed at Cas' heart for what Hannah had done, and for the fact that the other angel probably didn't even have the capacity to fully comprehend the betrayal herself. But he still had to ask, "Why Hannah? We were friends."

"That was before you freed Metatron," said Hannah simply, as if that explained everything, as if one action could wipe out an entire friendship as easily as erasing a chalkboard. "Before…" he left the rest of the thought unfinished. "The other angels, they hate you."

"And what about you?" asked Cas, thinking of the other former friend he would probably never get the chance to ask this question, and realizing that he wanted that answer even less than he wanted this one. "Do you hate me?"

Something flickered in the depths of Hannah's eyes then, but before she could respond, Ephram's voice cut across the silence.

"It doesn't matter. We took a vote. Democracy in action. And Hannah's doing the job."

That didn't sound like democracy to Cas; it sounded like a punishment.

"I won't give you Sam and Dean," said Castiel, chin held high and eyes blazing.

"Yes, you will."

AN: I know, I know, you knew all that already! Well, apart from Dean & Cas having a major blowout. But the things that were changed and highlighted here were important. Plus, writing those scenes in narrative form was a really cool writing exercise. Especially the Dean and Cas fight scene. Also, I did slip in a kind of nod to the attack dog spell in one of Cas' lines, if you caught that.

To clarify, I am by no means new to the Supernatural fandom, just to Supernatural fanfiction. I did also attend my first convention this year. It was awesome. I cosplayed as Claire, complete with a kick ass angel sword my brother made me, which Misha also thought was cool, which kind of made my day.

If you are here because you follow me, thank you, welcome back and I hope you enjoy this story as much as the others, and, I can hope, even notice the improvement in my writing over the last few years. If you've just stumbled upon my story in your hunt for new Supernatural fanfiction to read, welcome, I hope you have found what you're looking for and, if your other fandoms happen to include Harry Potter, Artemis Fowl, or Glee, feel free to check out my other stories, with the knowledge that all of them save the other one I just recently posted were at least started when I was 17/18 years old.

If you are familiar with my previous work, you may have noticed that this is my first M rated fic. While not a hard and fast rule, I've found that I tend to go about one rating up from the source material with my fanfiction. Supernatural is already pretty up there in terms of adult content, so it makes sense for me to rate this story M, so that I can have the full range of options of where to go with it.

No matter if you're an old friend or a new face (or avatar I guess, haha), I look forward to hearing from you about my first foray into writing for a "new" fandom in five years.

-SQ