Title:Sacrifice
Author:HigherMagic
Pairings: Demon!Dean/Fallen!Castiel, Demon!Sam/Fallen!Gabriel, mentions of Dean/Sam.
Rating: NC-17
Word Count: ~3,300
Spoilers: None (This is AU)
Summary: No one saw this coming, and it's only the start.
Notes/Warnings: Lots of bloody, gory, evil boys doing stuff to each other. Mpreg. Death of minor characters and brief, PG kissing between a minor and Dean.
Unbeta'd. All mistakes are my own.

Dean wakes up a few hours later, to the sound of Sam screaming. He winces and burrows deeper into Castiel's arms, knowing that what he's doing is the right thing – helping Sammy, making him better, is the right thing to do. The good thing to do.

He closes his eyes and covers his ears, and remembers why doing the right thing was always so fucking hard. Castiel turns closer, his eyes also closed, his breathing even in sleep or rest – Dean's not sure if he even needs sleep – and he curls one giant black wing around Dean, pulling him closer, and the sounds are muffled somewhat. The demon swallows and tries to find rest again.

"Dean!"

Sam's screaming his name. Dean can't take it – the mindless wails and grunts and screams, yes, but not his own name. Not his little brother calling out for his help, and being unable to do anything about it. The demon is up and out of bed before he can even think about it, but he doesn't make it to the door. He chokes, falling to his knees, feeling like a heavy weight is pressing against his chest, and looks behind him to see Castiel, arm outstretched and facing him, keeping him in place.

He growls threateningly. "Let me go, Castiel."

The Angel's eyes flash, and he swallows, but his hand doesn't move. "Come back to bed," he whispers, just as another scream ricochets through the house. Dean flinches, baring his teeth in a whine, on his hands and knees like a fucking animal, and everything that makes him Sam's – that makes him a big brother – rebels at being held down by another when Sam needs his help.

His body aches from Castiel's pleasure and touch, from what they did last night – Dean closes his eyes. It's been a long while since his body knew the feeling of being split open and torn apart, though his soul is well accustomed to it. It's purity and knowing, chastity and lust, burning him. He opens eyes that are just barely tinged black around the edge, and forces himself to his feet, and turns around to face Castiel.

"Why won't you let me see him?" he asks, and in his voice there is a challenge, even though he won't meet the Angel's eyes. Castiel sighs, getting to his feet, and his manner…it's so like Sam, like Castiel can't be pandering to Dean's every whim and sooner or later the demon's going to have to grow up. But in Castiel's eyes there is no exasperation and frustration – just pure, glowing love, and it hurts to look at, so Dean doesn't.

The demon closes his eyes when Castiel brushes fingers down the side of his face. "Sam's healing will still be in the early stages," Castiel whispers, brushing his lips against the corner of Dean's mouth. "Demon blood is a poison, Dean – and his blood is full of it. Gabriel will have to search through and destroy every part of Sam that is evil, filled with that taint, and the process could be long, and agonizing to watch. Until there is real hope, don't fill your heart with falsehoods that Sam is anything but okay right now."

Dean sighs, raising his hands to his face and framing his eyes with his hands, fingers digging into the corners of them, thumbs pressing against his cheeks. He takes a deep breath and it shakes, like he's fighting back tears. "I can't just listen to him like this, Cas," he says, voice rough like a blunt blade, and Castiel swallows.

"Do you want a distraction?" he asks, and the demon nods. "Maybe…maybe you could go training, or teach our son about other supernatural things. You were the best Hunter, Dean – you still are. Maybe…you can look back on your old life, and remember the way you used to be, if you meant what you said; that you wanted to be good again."

"I didn't say that," Dean can't help but point out, snorting bitterly. "I just said that I couldn't remember how." Castiel swallows again but doesn't say a thing. The Angel's fingers curl under Dean's palms and force his hands away from his face, and Castiel presses their cheeks and jaws together in a brief gesture of affection.

Finally, Dean draws away, and heads back to their bed. Castiel waves the door closed and soundproofs the room, just to be sure. The windows and curtains are open and the morning sunlight streaks in through the room, lighting up the bedroom and its occupants in soft dappling. Dean sits down in the middle of the bed, and reaches over to where his and Castiel's blades lie, side by side, and sets them down in front of him.

Castiel watches as Dean's hand hovers over the blades, and then finally he touches fingers to his own. Sigils flare to life on the side of the dark metal and Dean smiles, moving his fingers to the handle of his blade and then onto Castiel's. The Angel shivers, wings spreading a little, feeling the touch like a caress down his spine.

His eyes fall closed, and a muted whisper of the demon's name falls past his lips before he can stop himself.

Dean notices – his eyes flash over to the Angel and he smiles, curling three of his fingers around the handle now, twisting it a little in his warm grip with his thumb. "Can you feel me, Castiel?" The Angel's full name rolls off his tongue like a purr, and he grins when Castiel shudders in reply, folding his arms over his chest, digging nails into his biceps. His cheeks are starting to flush. "So pretty, Angel, and deadly, and powerful…" He moves his other hand and lays his palm on the blade, pressing down hard enough that his palm is sliced open, and Castiel gasps at the surprising intimacy of the action, of feeling Dean, all warm and slick around him. It's like Castiel's fucking him, and Dean probably knows that, the sneaky bastard.

Dean grips Castiel's blade in his blood slick hand, a little too tightly, so he cuts himself a little deeper, Castiel sinking deeper into the rift between his flesh, and the Angel shivers, going to the bed and into his demon's arms, wings flaring up to expose the underside for Dean's other hand, and the demon smiles, petting him, dragging his fingers loosely through the soft, thick feathers, and he tutts. "Haven't been taking care of yourself, Angel," he whispers, half-scolding, half stating fact. There's no threat in his voice so Castiel stays relaxed, even when Dean's hand skates down his chest and flattens over his curved belly. "It's not just you you're taking care of, you know."

"I know," the Angel replies, a little contrite, because it's true – he hasn't given a thought to his wings or his child, his only focus on escaping, then hiding, then rescuing Dean – there just hasn't been time to give himself a thought.

Dean makes a frustrated sound. "I can't believe I'm actually going to have to wait for him to come out," he says, still stroking over Castiel's stomach, and the Angel sits down, the heat of the moment dying for now, replaced with something softer and more like love and less like lust. Dean smiles and lays down next to him, forsaking Castiel's blade and grabbing his own, and he lays it over Castiel's stomach, resting his head on the Angel's chest. "In Hell, I could have just left the room for a day and come back when he was already born." He sighs, dragging the tip along the rise, poking it into Castiel's navel.

"But what good would that be?" Castiel says, because it seems like Dean's waiting for an answer, but the Angel's not sure what Dean wants him to say – there seems to be a slight tension under the demon's words, and Castiel has no way of telling what he's thinking – he's trying to give Dean's mind some privacy. "You were there for Malachai's birth."

Dean smiles. "Malachai," he whispers, moving the blade so it's laying in the junction between hip and thigh, away from the baby. "Yeah. That's true." Dean sighs. "I could feel you, you know. And him. And this little guy inside of you, when I was in Hell."

Castiel swallows. "Well, I did have your blade," he says.

Dean hums noncommittally, then sighs and nuzzles into Castiel's chest, his eyes closing. Castiel, unable to help himself, starts petting through Dean's hair gently, stroking it away from his face – Castiel had recreated it a little too long, maybe, but he likes it this length. He can actually drag his fingers through it this way.

"Where are we?" Dean asks after a moment, and Castiel looks at his mate's face, but Dean's eyes are closed, his expression relaxed, even if there is a little furrow in his brow, and Castiel strokes his thumb over it until it smoothes out.

The Seraph smiles a little. "I have no idea," he replies honestly. "If I had to guess, I'd say we are in a recreated New Zealand, but somewhere in the In-Between that isn't actually on Earth."

"No shit," Dean replies, sounding amused and awed all at once, and then he sits up. "I…I don't even know…" He swallows. "I want to go see Bobby. And Ellen and Jo and…" He swallows again. "But they wouldn't be very happy to see me, now would they?" Castiel sits up too, stroking a hand down Dean's back to soothe him, but he doesn't know what to say to make things better so he doesn't say anything at all. Dean winces when a particularly loud scream makes it through Castiel's soundproofing. The Angel jerks, not having expected the sound, and the soundproofing falls along with his concentration, letting in the sounds of more panicked yells that are not Sam's. Immediately Dean pushes Castiel to one side and shoves himself to his feet, ready to go investigating, and Castiel's following right behind.

Luke, Uriel's son, and Sofia, Anna's daughter, are both collapsed on the ground, shivering and shaking as though struck with fever. Immediately Dean rushes to their sides, feeling at their foreheads, his face a mask of concern and anxiety. Malachai comes rushing from the direction of Sam's room.

"Did you see what happened?" Dean asks his son.

Malachai looks panicked and worried, his feathers standing up on his flight pair of wings, his defensive pair flared out. "There was this…" He shakes his head, pressing his fingers to his temple. "Gabriel was doing something to Sam, and this huge black smoke cloud came out of Sam's mouth, and then…then I heard Luke and Sofia screaming."

"Black smoke cloud?" Dean repeats, his voice low with dread and fear, eyes wide, and Malachai nods. Dean then turns to Castiel. "Find out what the fuck's going on," he demands, his voice hard and gruff and Castiel doesn't even think about disobeying – taking orders all those years, one does develop a little habit of obeying. He rushes to Sam's room and finds Gabriel inside with Tristan and Evelyn, who are standing like sentinels on either side of their Sire, and Gabriel's arm is buried deep in Sam's chest, his face twisted into an expression of concentration.

"Brother," Castiel whispers, hurrying forward so he stands and looks over Gabriel's shoulder. "What is happening?"

"The evil is trying to escape," Gabriel mutters in reply, his voice strained like he is trying to lift a very heavy weight. "I tried taking pieces but they slid out of my grasp and fled his body. I didn't think to seal him inside and…fuck, now there's so many holes. Like he's just leaking out of his soul."

Castiel swallows, because no part of that sounds good. Sam's still screaming mindlessly, his head thrown up into the air, sweat dripping off his face, and there's blood around his ears, making the headphones slick and falling out, and there's blood where the ropes are cutting into him because he's struggling so violently. Tristan has a hand on his Sire's shoulder, but he's not holding him down or doing anything to help. The twins' faces are stoic.

Outside, Dean recoils when something inside of Luke and Sofia rises up and claws at him, latching onto his essence like the demon's outside of his body. The children's eyes flare open yellow and they grin at him. "Mine," Sofia whispers, grabbing hold of Dean's neck and pulling him down, and she's fucking strong for a child, and Dean's too shocked to fight back in time to avoid her kiss. It tastes like ash and blood and when he pushes her away, he sees blood around her mouth and knows it's on his too. She's smiling like she's triumphant. "You'll be mine again, Dean," she whispers once more, and then her body convulses, her eyes roll back into her head, and she lays still. Luke follows her not long after.

Before Dean can even think about the fact that two children just died right in front of him, because of something he may have directly or indirectly caused, he's suddenly overcome with a feeling of heaviness, like he's just swallowed a rock and it's sitting heavy and solid in his stomach. He coughs, dry-heaving, trying to get rid of the sensation but it just sinks deeper, and grows barbs and latches onto his insides, cutting him open and soaking in his blood. When Dean coughs again, blood sprays out onto the back of his hand and the female half breed's bloody feathers. Malachai's just staring at him in horror.

Sam suddenly goes limp and Gabriel draws his hand out very slowly, carefully like he's trying to dislodge a tiny piece of a structure without having the whole damn thing collapse on him, and sighs in relief when nothing happens with the removal of his hand. "There," he whispers. "It's okay."

"Sam is healed?"

Gabriel shakes his head. "No, but I managed to stop whatever the fuck was happening." Absently, he wipes his hand on his jeans, though there is nothing there but his own skin. "This won't work, Castiel," he says, shaking his head again and turning to the Seraph. "We need to try something else."

"Cas." The Angel turns, finds Dean leaning heavily against the doorframe, looking almost drunk. The demon's so out of it – one eye is black, the other is a weird mix that Castiel's never seen before. Almost amber, with dirt inside of it or an insect of green. It's strange and disconcerting.

Dean turns away from those gathered in the room, looking back towards the bodies, and takes a deep breath. Castiel then notices the blood around his mouth. "The…Luke and Sofia…" Dean coughs again, wincing as every movement makes his gut and chest ache, and he slides down the side of the doorframe, holding his hand up his mouth. Malachai joins him not seconds later, a hand on his father's forehead, his eyes closed, and Dean's coughing abates for a second, his eyes closed at the temporary relief.

"What happened to them?" Castiel asks, afraid of the answer.

Dean's eyes open again and he laughs – it's a harsh, angry sound. "They're fucking dead, that's what happened." He holds his hands to his head, closing his eyes once more. "Fuck…this is my fault. I was meant to protect them."

"No one could have foreseen this." Gabriel's voice is low and he steps away from Sam. The twins follow along closely behind, shadowing and flanking him like he's some sort of twisted mob boss. His eyes are wide and fixed on the demon. "Castiel, look."

The Seraph's brow furrows in confusion, but Gabriel won't explain more – he just jerks his head towards Dean again with a meaningful look. The Seraph keeps looking, but doesn't see it – Dean just looks sick, like he's coming down with a fever and the only bad thing about that is that he's never heard of a demon getting sick before. Then, his eyes widen when something…moves inside of his mate, and Dean moans softly again, resting his forehead against his son's neck.

"Amber," he whispers, his wings falling in understanding. "No…" He looks to Gabriel, whose expression is grim.

There, amongst the black of Dean's soul, swirls the beginning of a marbled yellow taint.

Anna had not been there when her daughter died. Dean takes it on himself to tell her the news, and then he holds her when she cries, her wings shaking and her body heaving with sobs. Castiel's just selfishly glad that Uriel had died in the escape attempt, because he does not think Dean could have handled that a second time. Or perhaps it would have been better, if Uriel had been angry and blamed him and taken it out on Dean. Castiel knows his mate has a bit of a self-loathing streak inside of him, and craves punishment for things he thinks is his fault. Still, that doesn't mean Castiel wants it to happen.

They salt and burn Luke and Sofia's bodies because there are some things that Dean will not let them risk, and the house is quiet for a long time after that, before Dean finally asks, "What now?"

"Now?" Gabriel sighs, sitting back. "Now we try something else." Dean looks over at him, surprised. "I knew you both before you went to Hell, Dean," Gabriel says quietly. "There is good in Sam, and he is my mate, and I suppose, in some twisted kind of strange not-healthy way, I care about him. I suppose I have to love him, or my children wouldn't exist. I want him to survive this and make it out alive as much as you do."

Dean makes a surprised, grateful noise, and presses his forehead against Gabriel's briefly. "But whatever it was you tried, it didn't work…" He winces, cutting himself off, rubbing at his chest, which has been hurting ever since the incident with Luke and Sofia.

"There are other things we can try, and this time I shall be much more careful." Gabriel's voice is hard and determined, and Dean swallows, the desire to save Sammy warring with the need to make sure everyone is kept safe and the tragedy does not repeat itself, but eventually he nods, because Sam is…is Sam. End of. "And I did manage to get rid of a good portion of it already."

"Where did it go?" Dean asks. "It can't have just disappeared."

The table is silent, and Castiel can feel Gabriel's eyes boring into the side of his face for a long while, before he slides his hand forward and takes Dean's in his own, his wing curving around the demon's shoulders.

"We don't know," he says, "but we're working on it."

Dean nods, accepting the lie. It's the first time Castiel's ever lied to Dean, and he hates the feeling of it, how it settles like sour honey in the back of his throat. He sighs, and presses his nose into Dean's cheek, holding him close, and prays for the first time in a long time, that they make it out of this okay. That they will all survive, and that Dean gets his brother back, no matter what that means for Castiel. He just wants his demon, his mate, to be happy.

He thinks Dean deserves at least that.