The first time Dean kisses Cas is after a failed mission, after they lost five of their guys and Cas nearly lost an arm.

Dean hauls him back into their camp, Cas's undamaged arm draped over his shoulder, barking orders at people to get out of the way. He takes Cas into his private cabin and deposits him on the bed, shouting at Chuck to bring him bandages and a water bottle. Cas is so out of it that he doesn't even move as Dean practically rips the bloodied shirt off him.

"Dammit, Cas," Dean breathes, eyes running over the shredded flesh of Cas's right arm.

Cas just smiles a lopsided grin and turns his vacant eyes onto Dean. Dean bites his lip and puts a hand on Cas's cheek, cupping it and running a finer over the stubble that lines his friend's sallow cheeks.

Even though Dean will never admit it fully, he blames himself for what has happened to Cas, for how far the angel has fallen. After all they've been through, he still can't believe that Cas is still with him. He would have left ages ago were he Cas, but Cas had stayed, stayed through Dean losing Sam, though the long nights when it was Dean and a bottle of whiskey and Cas outside Dean's cabin, standing watch, guarding his charge until the very end.

Cas is just so human now that it hurst Dean. It hurts to watch Cas drown himself in pills and booze, to slip away and try to lose himself in a night of rigorous sex with whoever had been nearest when he was about to turn in for the night. Dean has told him before to lay off, to just take a week and not put anything but decent food into his broken body. Cas had waved him off with the canister of white pills in his hand and then Dean had watched as he downed the whole thing. He'll never forget that night, how he was the one who stood guard over Cas as the fallen angel puked his insides into the bucket Dean was holding.

As Dean dresses Cas's wound now, he's sorta glad that Cas decided to overdose on the ride back. He had been moaning and groaning something awful after that Croat had come at him with that knife. Dean had shot him down before he could do anymore damage to Cas's already damaged body.

Cas coughs as Dean pulls the bandage tight around his bicep and Dean can tell what is coming next. He grabs a nearby bucket and holds it under Cas as Cas wretches into it, his body shaking from the force of it. Dean places a hand on his back to steady him as Cas's body expels the drugs from his system yet again.

He goes still and Dean takes the bucket away. Cas slumps forward and Dean has to catch him before he falls right into the bucket of his own sick. Cas moans against his shoulder and Dean eases him back onto the bed, Dean's bed actually, not that he minds, it is Cas after all.

"Dean?" Cas's voice is shaky and he licks his lips a few times.

"I'm here," Dean says, sitting down next to Cas and offering him some water.

Cas takes the bottle with shaky hands. He takes a few deep gulps and then swishes around a mouthful, which he spits into the bucket. He then sits back, the bed dipping slightly as he puts his back against the wall.

"Feeling better?" Dean asks.

"I just threw up fucking everywhere," Cas hisses, "How do you think I'm feeling?"

Dean cracks a small smile, but there's still that part of him that will never get used to those sort of profanities coming from Cas's mouth. Dean thinks often about how pure Cas used to be, how unscathed he was before this, before the temple of his body crumbled to the ground, before Dean brought him crashing to the earth to roll among the sin and the filth of the new world that they were facing.

"Shit," Cas groans and he tries to move his banged up arm.

Dean puts a hand on his arm. "Stay put, buddy. You lost a lot of blood."

Cas moves away from Dean's touch. "Don't tell me what to do."

He gets up and starts to leave, but wobbles and falls to the ground of the cabin with a thud and then a hiss of, "Fuck." Dean rushes to help him up and Cas reluctantly lets Dean carry him back to the bed and deposit him upon it. He flops back onto Dean's pillow and stares up at the ceiling. Dean sits on the edge of the bed near Cas's legs and Cas gives him a look before closing his eyes.

Dean pushes Cas's legs away so that he can lie down as well, his head near Cas's ankles. He tugs the boots off Cas's feet, saying, "Not in my bed, and if you're staying here for the night, you better not snore, got it?"

"I never snore," Cas retorts and for a second it sounds like old Cas, but then this Cas is shifting so that his feet are resting on Dean's face, his dirty socks practically in Dean's mouth.

Dean shoves him off with a, "Fuck you, Cas."

"If you want," Cas replies, and Dean can see his grin in the fading light of the cabin.

He sighs and turns onto his stomach, purposely ignoring Cas's comment. They have this thing that they do sometimes, after Cas comes back from a massive orgy or Dean stumbles out from yet another chick's cabin. They sorta tease each other a lot and flirt shamelessly in front of the rest of the camp residents. Everyone assumes that Dean and Cas have been fucking each other's brains out for a while, but they haven't. They just poke and prod at each other, and it's mostly Cas, who seems really into the whole sex thing now that he's completely human. Sure Dean had slapped Cas's ass that one time in front of Chuck, but it didn't mean anything, they were still just Dean and Cas.

The bed shifts as Cas moves and Dean turns over onto his back to watch him as he sits up. Cas leans over and Dean is prepared to grab the bucket again, but Cas just gets up and stretches. Dean tries not to watch as the muscles pop and stretch under Cas's thin skin.

Cas must catch him staring, because he cracks one of his odd smiles again and then he says, "Enjoying the view?"

"Shut up," Dean groans, throwing an arm over his head.

He hears the floorboards creak as Cas steps over them and then suddenly Dean feels warm breath against his lips, and then Cas's chapped lips are against his own. Dean's arm slips from his face and he's not sure how to respond to this, to Cas's mouth against his, to the most intimate gesture that the ex angel has ever given him. Part of him wants to shove Cas off, to kick him hard in the balls and tell him to fuck off, but another part wants to grab Cas by the lapels of his jacket and tug him closer.

He does neither and Cas finally pulls away after a bit, leaving Dean lying there as he limps out of Dean's cabin. Dean spends the rest of the night tossing and turning, trying to deny the fact that his dreams are filled with Cas and that when he wakes, the first thing he does is raise his fingers to his lips and miss the soft pressure of Cas's own lips there.

The second time Dean kisses Cas, he does it because he's jealous.

Things had been going pretty good, they had completed a couple successful missions, and Cas's arm is healing well. He still gripes about it to Dean and whoever else would listen, but Dean can tell that he is feeling slightly better. He even began to notice that Cas isn't taking as many pills as usual, and that there aren't so many empty beer bottles tossed out with the trash the next morning, although Dean does notice the used condoms that fill Cas's trash bin. What he doesn't know what to do with, is the strange feeling in his chest as he empties them into their compost pile. If he didn't know better, he'd say it was jealousy.

It becomes obvious what it is when Dean walks in on Cas in the middle of fucking around with some chick. They are both shirtless and Cas's mouth is latched onto her neck, sucking noisily as she moans loudly. Dean watches as Cas grinds his hips into hers, her fingers carding through Cas's messy hair as a string of profanities erupts from her mouth.

Dean's fists clench and he feels something almost like rage filling his veins. He doesn't want her touching Cas, he doesn't want her mouth on Cas's skin, doesn't want her teeth to mark him up, for her nails to scratch and fingers to pry. He thinks about going and just yanking her off Cas, throwing her out of the cabin and assigning her to the dirtiest, grossest jobs of the camp. But he doesn't, instead he just coughs loudly.

Cas pulls away from the girl with a wet popping noise and they both turn to look at Dean. As soon as Cas meets Dean's eyes, that strange smile comes to his parched lips again and he turns over so that he's lying between the woman's legs, his cheek against one of her thighs.

"Wanna join us?" Cas asks.

Dean narrows his eyes and points to the girl. "Get out," he hisses.

She looks uncertainly down at Cas, who is watching Dean through lidded eyes. Cas sighs loudly and then he gets up, offering a hand to the girl and then her shirt, which she pulls on hastily, pushing past Dean, who glares daggers at her. The door shuts behind her with a click and Dean and Cas are left alone in Cas's cabin, which smells like beer and sex.

Cas crosses his arms and looks at Dean. "Trying to spoil my fun?" he asks. Then he smiles, "Or did you just want me all to yourself?"

Dean gulps and hopes that it's not too obvious that his eyes have been traveling over Cas's shoulders and torso hungrily. Cas notices though, as he always does, and Dean sees that smile stretch across Cas's face. He bites his lip and then he's walking toward Cas and crashing their mouths together.

He can taste all the usual things on Cas's tongue, the booze and the pills, but he can also taste the woman in his mouth and he wants that taste out. So he scrapes Cas's mouth clean with his teeth and tongue, turning the fallen angel inside and out. Cas moans and Dean's mind catches up with his body.

He pulls away from Cas quickly and they stare at each other. Cas's lips are swollen, parted and wet as he stares at Dean with something different in his dull eyes. Dean dares to think that it's a spark, that he can see his Castiel somewhere in there, under the pills and the liquor, that all he needs to do is scrub him clean and take away all the grime stuck to Cas's body, that he could somehow raise Cas from the pit he's fallen into.

Cas steps closer to him and Dean backs away. He bolts out of the cabin and runs, runs through the camp until he finds himself back at his own cabin. For some reason he's scared, he's scared of what just happened, of how he might feel about Cas, about the angel that has always stood by his side through thick and thin. He goes to sleep that night and has a memory instead of a dream.

In it Cas's eyes are clear, his smile real, but Dean can't reach him. It's almost like he's a ghost and every time Dean reaches for him, he slips through his fingers. Then it switches to his new Cas, but this time Cas's eyes hold nothing, they are cold and dark, his mouth slightly parted as a drop of blood drips from it and onto the ground where he lies fallen. Dean can see his own hands holding Cas's body and he can feel the cry ripped from his throat. Dean wakes in a cold sweat and doesn't sleep again for two days.

The first time Dean and Cas have sex is during the early hours of morning, after the night, which brought more death into the camp after yet another failed mission.

Dean finds Cas huddled outside his cabin after they get back into camp. His head is in his hands and Dean can see his body shaking from the small sobs that seep past his fingers, which cover his mouth. Cas had been careless during the mission, he had turned his back, so to speak, and they had lost more people, a lot of people actually.

Dean glances around once before he goes over to Cas, placing a hand on his friend's shaking shoulder. Cas turns his tear streaked face toward Dean. His eyes are bloodshot and his bottom lip quivers slightly. The sight makes Dean's heart hurt and he puts a hand out to Cas, who grips it tightly. Dean pulls him up and then takes him into his arms, letting Cas bury his face in his shoulder, feeling the wetness against his skin as Cas presses their cheeks together.

Cas is shaking so much that it surprises Dean that he can even stand still. Dean can feel Cas's breath beating against his skin and then the strangled, "I'm so sorry, Dean."

Dean grips Cas tightly as Cas continues to mutter apologies through his tears. Finally, when Dean can't stand listening to the broken voice anymore, he pulls Cas from him and presses his lips against the fallen angel's in order to quiet him. Cas sags against him and Dean knows the people still outside are watching, but he doesn't care, doesn't care that they watch as Dean practically drags Cas to his cabin and slams the door loudly.

Cas's mouth is wet and wonderful, but Dean can taste all the foreign substances on his tongue. He wants to kiss them all away, run his hands over Cas's broken body and rebuild him until Dean can have his Cas back, all bright eyes and innocence.

Cas gasps against Dean's mouth as Dean grinds their hips together and then Dean is shrugging his jacket off and ripping Cas's own jacket down his shoulders. Cas helps to get rid of their ratty shirts next, and then they're maneuvering their way to Cas's bed in the corner. Dean latches his mouth onto the pale column of Cas's neck and sucks hard, forming a dark bruise and making Cas arch up. Dean inspects his work and a smile comes to his face, because this is how he wanted Cas to have broken, by his hands, his mouth, him, not all the pills and the women. He wanted to be the one to make Cas fall, but instead he's here now to catch him.

Dean's hands are everywhere at once, running over Cas's skin, feeling the scars that stand out under his fingers, the dark spots under his ribs, shadows on the pale skin. Dean drags his fingers over each of Cas's ribs and then his mouth, kissing each one, feeling Cas tremble under him.

"Dean," Cas whines, his hands scrambling on Dean's back.

"Shhhh," Dean whispers against Cas's shaking stomach.

"I want you. Please Dean. Please."

Dean's never heard Cas like this before. He's begging, mewling every time Dean touches him. He arches into the drag of Dean's fingers over a puckered nipple. Dean replaces his hand with his mouth and Cas moans loudly, bucking up from the bed and slamming his hips into Dean's. Dean growls and then he sits up so that he can shimmy his jeans off. Cas does the same with his, sliding them down his legs, and pulling off his boxers in the process. Dean's eyes travel possessively over Cas's lower body and Cas grins wolfishly up at him before yanking Dean's boxer's down, taking care to ease them over his erection.

They take a minute to grind together slowly, letting their dicks drag against each other, gasping and groaning with every touch, and then Cas is angling his hips just so and Dean gets the idea, although he's not sure where to go with it. Cas can sense his hesitance and he pushes against Dean's shoulders so that Dean sits back on his haunches. He watches as Cas reaches into the top drawer of the nightstand next to the bed. He pulls out a bottle filled with what looks like lotion and Dean's heart hammers in his chest and he realizes what it is.

Cas meets his eyes as he uncaps the bottle and holds Dean's gaze as he sticks his fingers into the lube. He sits back and stretches his legs wide, fingers poised over his hole. Dean watches with an open mouth as Cas slips a finger inside himself. His eyebrows twitch downward slightly as he slips another finger inside, stretching and scissoring in a such a way that Dean knows Cas has done this before. The thought that someone else might have had Cas like this makes Dean's stomach churn angrily.

He slaps Cas's hand away and replaces it with his own, slipping two and then three fingers into Cas and making Cas cry out. Dean shushes him with his mouth, and Cas whimpers against his lips as Dean adds a fourth finger, stretching Cas wide and making him buck up from the bed with a strangled sound.

"Dean," Cas whines "Dean please. Now Dean."

Dean moves his hand to his own cock, greasing it from base to tip as he drinks in the sight of Cas laid out before him, entirely his, entirely broken, entirely fallen, begging for Dean to pleasure him, to make him forget about everything. Dean leans forward and captures Cas's lips in a soft kiss as he slides into him. Cas's mouth falls open against Dean's and Dean can hear the tiny noises spilling from the back of Cas's throat. He thrusts his hips hard into Cas and Cas cries out.

"Fuck, Dean. Oh god, oh god, right there, Dean."

Dean's name is a plea on Cas's lips and Dean growls against Cas's mouth before bucking into him again. They create a sort of rhythm. Cas's nails scrape down Dean's back as he meets Dean thrust for thrust, arching upward as Dean snaps his hips downward. Cas presses his lips to Dean's shoulder, his collar bone, kissing everywhere he can reach and whispering words against Dean's heated skin. Dean doesn't recognize them and then he realizes that it must be Enochian. He does hear three words clearly though as Cas repeats them over and over again as he rolls his hips up, "I love you. I love you. I love you."

"I know, baby. I know," Dean says against Cas's collar bone.

He kisses Cas again and then Dean feels wetness against his stomach. Cas throws his head back and fucks himself against Dean's cock particularly hard as he rides out his orgasm. Dean follows soon after, spiraling into the fire that burns in his body and then falling atop Cas as he comes back down.

Cas kisses his shoulder and helps Dean to ease out of him. Suddenly the cabin is bitter cold, the only warmth is Cas and Dean runs toward it, pulling Cas into his arms and burying his head under Cas's chin. Cas rubs soothing circles up and down his back and Dean should be the one comforting, not Cas, Dean is supposed to be strong for them both. He's supposed to raise Cas back up again, to bring him out of the pit he's fallen into, to give him back his wings and watch him soar. But he can't, he can't do it because he doesn't know how, and all he knows is Cas's arms surrounding him and Cas's rough voice whispering those three words to him again, each one searing into Dean's brain and Dean knows this is the point where he breaks.

The last time Dean and Cas are together is right before they are separated forever.

The entire day has been so fucked up that Dean almost doesn't know what to do. There are two of him and the time has finally come to face Sammy, to put an end to everything that he started by saying no.

Cas is with him until they leave, there to comfort him with his lips and his body, his strong hands supporting Dean as they fall together again, slow movements and those three words whispered to each other, again and again, a conformation.

Dean kisses Cas in front of everyone before they start off, only making sure that his past self doesn't see, doesn't see how far he's fallen, how far he's let Cas fall. The kiss is long and wet, because he can't keep the tears from spilling and he's never been more thankful that it's dark, so that the others won't see that he's broken now too. Then Cas is gone, heading off to take his past self to the place where they will most likely all die, where they will die, because Dean knows that it's the end, for real this time, that this could never last, that Cas could never last. He knows he's broken inside, and that not even Cas can mend him, because Cas is broken as well. They broke like they fell, together. And Dean knows that this is always how it's going to end, no matter how they get here, they will always break, and they will always end up here.