Title: Three's Not a Crowd

Rating: M

Pairing(s): Dean Winchester/Sam Winchester/Castiel

Warnings: violence, voyeur!Castiel, masturbation, sexual content, bottom!Sam

Disclaimer: Don't own 'em - not making any money off 'em. Dern it.

Summary: Sam loves both Dean and Castiel, but they love each other. Neither of them would ever want Sam, or at least that what he thinks. What happens when Sam runs away only to be captured by a demon?

Notes: For the Wincestiel Big Bang 2013.

Chapter 1

Sam watches Dean and Castiel dance around each other, practically fucking with their eyes. It's pathetic, Sam thinks. He shakes his head. Who's he kidding? He's the pathetic one. He's the one who lusts after both an angel and his own brother, who only have eyes for each other.

Sam looks down at his hands so he doesn't have to look at the objects of his devotion. Sam knows it's not simple lust. If it was, Sam would be fine. He wouldn't have this pain in his chest that makes him feel as if his world is ending. Sam knows he's in love with two people he shouldn't be in love with: Dean and Castiel.

Dean –his older brother. Dean –his constant protector. Dean – the most loyal and bravest person Sam knows. Dean – who would never ever think of his family in the dirty way Sam thinks of it.

And then there's Castiel – an angel of the Lord. It's laughable to believe an angel would stoop to have sex, never mind love, with the 'boy with the demon blood.' Like Castiel said, Sam is an abomination. He knows Castiel will never look at him the way he looks at Dean. All Castiel will ever do is tolerate Sam, and it will only ever be for Dean's sake.

Sam's heart hurts, but he knows it's the truth. He's not worthy of either of them. He can't imagine a more perfect match then Dean and Castiel. A match made in heaven, Sam thinks wanly.

Sam feels tears coming and shuts himself in the bathroom so Dean doesn't worry. Ever since the gates of Hell were permanently closed, Dean seems to always worry. Sam makes sure his sobbing his silent. No reason to alert angel ears of Sam's predicament.

Sam catches his reflection. His red eyes stare back at him, and he knows he can't go out there looking like this. No excuse would satisfy Dean if he saw what was in Sam's eyes. As he washes his face, Sam comes to a decision. He will make sure Dean and Castiel get together, no matter what. If the two people he loves most in the world can't love him the way he loves them, at least he'll know they're together. He'll be content knowing they are happy. Sam tries to believe his own lies, but can still feel a lingering ache in his chest.

Sam has set it all in motion. Castiel is going to go into the motel room after Sam calls him and will then see Dean all…exposed. Hopefully, despite being an angel, Castiel will still act on basic human primal needs. Hopefully, Sam thinks again.

Sam knows it isn't his best plan, but it's the only one he could come up with, with such short notice. He wants to get the two of them together as quickly as possible.

He heads to the door of the motel, telling Dean he's going to the library to research their current hunt – a ghost that seems to be going after sisters – and as he leaves, he hears the shower start. He gives Dean ten minutes, knowing his brother likes to jerk off in there, after hearing him often enough. Sam flushes at the memory, feeling himself harden slightly. He shakes his head. Now is not the time for that.

Once he's sure Dean is out of the shower and toweling off, he calls Castiel on the cell phone that Dean made sure to tell him to keep, in case prayer wasn't a viable option to get a hold of the angel for whatever reason. Sam is grateful now. This plan would have been trickier without the cell.

"What?"

Sam smiles at Cas's confused voice. Even now, Cas still has difficulty understanding basic human things. "Hey Cas, are you busy?"

"Of course not, Sam."

Castiel's suddenly warm voice makes Sam smile, but doesn't dare think it's anything more than it is. "I'm making a run to the library. Can—"

"Why are you running to the library?" Castiel asks.

Sam shakes his head despite Castiel not being able to see. "Never mind Cas, figure of speech. Anyways, can you pop into the motel room quickly? Dean needs to talk to you."

The phone goes dead right away and Sam assumes Castiel popped into the room as soon as Sam suggested it. Sam ignores the usual clench of his heart at the fact that Cas moved so quickly for Dean. It isn't anything he isn't used to, after all.

He just wishes…

Sam shakes the thought away. There was no use wishing for something that could never be. This was his lot in life and Sam would just have to deal with it.

Sam takes a breath as he stares at the door to the motel. He's not sure what he's going to find, but he knows he needs to be prepared. He eases the door open and cautiously looks inside the room.

Dean and Castiel are curled against each other with Dean's head lying on Castiel's chest. The angel's eyes are wide open, and his eyes are soft as he stares at would never admit to cuddling, but he obviously is. Sam smiles a sad smile.

Sam thinks about leaving them alone, but they need to salt and burn the ghost before someone else dies. Besides, Castiel watches him, and there's a cautious look in his eyes.

Sam sends a reassuring look to the angel. "Can you wake Dean up? We need to take care of the ghost."

Castiel nods, but he seems uncomfortable with Sam catching them together; he shakes Dean awake.

"Whaa?" Dean asks, rubbing his eyes.

Dean really does make an adorable picture when he first wakes up.

Dean's eyes widen when he notices Sam in the room. He shoots up like a poptart. "Sammy, I— um… I can explain."

Sam rolls his eyes. "Dean, I sent Castiel to your room, knowing you'd be naked. Don't you think I knew what would happen?"

"You planned this?" Dean asks, blinking his eyes disbelievingly.

"Of course, seeing how you guys act around each other was kind of sickening. The way you guys were going, it would have taken ages for you to hook up. At least you'll get rid of some of the tension and won't be so painfully nauseating."

"We are not nauseating," Dean says grumpily.

"You really are," Sam disputes.

Castiel remains silent, watching the brothers' banter.

"You okay, Cas?" Sam asks.

"Yes, but are you sure you're okay with this Sam? I don't want you to be uncomfortable."

If only Castiel knew. Sam will be uncomfortable all right, but it will be because of a whole lot of different reasons. "I'm fine Cas. I'm glad you two are finally together." Sam smiles, and he can almost believe it.

"Enough chick flick moments, dudes."

Sam rolls his eyes at Dean. They talk about the ghost and discover where the body is buried. They slot in their usual roles as if nothing's changed.

Sam thinks it won't be so bad. From afar, he's watched Dean and has been in love with him for years, before Stanford even. He's watched Dean be with girls and guys. Even though he knew Dean never really loved them, it was still painful to see.

Although he's only known Castiel for a few years, he has had feelings for him for awhile as well. Castiel went against everything he knew to stand by the brothers. The angel is extremely gentle most times, but is a warrior when it comes to protecting Dean and Sam. What's not to love? So what if he's going to be forced to watch them be all coupley? How hard can it really be?

It turns out... very hard.

Sam has always been an early riser due to their dad's strict regimen. That continued through Stanford because he almost always had classes at 8:00 AM. Dean, on the other hand, despite being able to get up early, enjoys sleeping in when he has the chance.

Most mornings, Sam is awake before Dean and just stays in bed so he can watch his brother undisturbed. It's the only time Sam can watch Dean without getting weird looks or getting caught.

The sound of flapping wings catches his attention, and Castiel, who probably doesn't realize Sam's awake, leans down and kisses Dean gently on the lips.

Sam watches as Dean's eyes quickly pop open before pulling Castiel down on top of him. Sam watches as they kiss passionately; he wants to look away, but finds he can't. Sam tries to catch the tears rolling down his cheeks. He quickly turns to lie on his other side so he's facing the wall instead of his brother and Castiel. The sound of gentle kissing that causes Sam's heart to ache doesn't stop, so they obviously don't notice Sam's anguish.

Sam's surprised that Castiel's angel senses aren't kicking in, but he's probably too focused on making Dean groan so deliciously to notice. Despite his pillow covered ears, Sam can't drown out the sounds of pleasure from Dean's bed.

That little scene happens more than once, and it isn't the worst of it.

More times than Sam would like to remember, Dean goes into the shower alone, but soon the bathroom echoes with groans and yells of pleasure. When the door opens, Dean and Castiel both come out wet. Dean's cheeks are flushed and he usually wears a smug grin, while Castiel sports unhealed bruises that are definitely hickeys and seems very pleased with himself.

During these showers, Sam puts his headphones on and cranks his music up as loud as he can. It doesn't change the fact that Sam knows what happens behind the thin door.

The first time Sam and Dean go to a bar since Dean and Castiel started sleeping together, Sam thought he'd get a blessed reprieve from the happy couple. But alas, no. Castiel always joins them quickly and keeps Dean's attention solely focused on him. It's as if Castiel is worried Dean is going to do something with the girls at the bar if he's not there to remind Dean what he has.

That is never going to happen. For all of Dean's faults, he is extremely loyal to the people he cares about and never wavers in that loyalty, no matter what.

Sam is forced to watch Dean swallow Castiel's tongue as they kiss at the bar time and time again. Sam sees how all the girls pout when they learn that Dean is very much taken. It almost makes Sam smirk. That is, until the girls decide to try their luck out on Sam.

Dean always laughs, but at the same time he seems bothered by the attention Sam's receiving. Meanwhile, Castiel watches him with those clear blue eyes that seem to see everything. The angel frowns as the girls hang over him. He continuously tries to draw Sam's attention back to the two of them, while Sam tries to enjoy the girls' presence. All in all, it just makes Sam want what he can't have even more.

Sam always tries to be polite, but usually ends up being blunt to get the girls to leave him alone.

Although Dean and Sam still spend time together, (after all, they're constantly stuck in a car together 12 hours a day), more times than not, Dean ditches Sam once they check in for some alone time with Castiel.

One would think that would be easier on Sam. He wouldn't have to see what Castiel and Dean are doing, right? It has to be easier to handle, right? Wrong! All that does is it allows for Sam's imagination to take over. And Sam has always had a very active imagination. In some ways, it is harder.

The worst and best thing that Sam has had to deal with was the time he walked in on the happy couple in the throes of passion.

Sam will always remember the one and only time he walked in on them. Sam had gone to get food and didn't think about knocking when he got back to the motel room.

When Sam stepped into the room, Dean was inside of Castiel, thrusting hard. Castiel's back was arched with his eyes closed. Dean's head was low as he bit down on Castiel's collarbone. Sam could see Castiel's trembling fingers cradling Dean's cheek. Little red marks claimed the skin around Dean's throat and shoulders. There was a big purple one where Sam used to bury his face when he cried about mom.

Sam was forced to watch as both Castiel and Dean came together. He was struck with the beauty of it all. They really did belong with each other. If anything drove that point home to Sam, it was seeing this. He knew then what he was missing out on, but he also has a memory to treasure for the rest of his life.

Sam gulped as their breathing evened out. He turned away to close the door and knew his cheeks were stained red.

"Enjoyed the show, Sammy?" Dean asked from the other side of the door. Sam could hear the smirk in his voice.

Sam almost said 'yes,' wanting his ugly secret to be out in the open. He caught the word in his mouth before he could humiliate himself. "Not really, jerk," Sam mumbled, but the usual teasing behind the name wasn't there, as he slumped against the door.

Dean didn't seem to notice. "Bitch," he shot back.

"Want food?" he asks as his eyes stay averted. Sam desperately wanted to pretend the whole thing didn't happen.

"Sure," Dean says as if everything is just dandy.

Sam's smile is forced as Castiel continues to watch him with that unwavering gaze. Sam wants to drop his eyes to the angel's waist, which is covered, but forces himself to keep them safely on the impassive face. Sam's eyes swivel as Dean quickly gets dressed. He blushes at Dean's lack of modesty. Castiel, on the other hand, simply poofs his clothes on. They all go to the table to eat.

Sam tries to be okay with Dean and Castiel's relationship, but it hurts. Sometimes it feels as if Dean is purposely going out of his way to shove their relationship in Sam's face. Sam doesn't want to believe Dean would do that, but it's pretty hard to see anything different.

Sam walks into a room, Dean pounces on Castiel. Sam looks towards the two of them, and suddenly Dean is pulling Castiel on his lap and kissing him fiercely.

Sam really doesn't know what's gotten into his brother, a person who has never been overly demonstrative. Castiel doesn't appear to be harboring the same competitive animosity Dean does; he seems to be just going along for the ride.

Sam stops sleeping. Every time he closes his eyes, he imagines himself in between Dean and Castiel, feeling two pairs of hands on him. Castiel's tongue would fuck his mouth while Dean's mouth worked his hard cock. They would work together to bring him unbelievable ecstasy. Sam would then sigh in contentment before allowing his mouth to suckle on Castiel's pale neck. The little mewls Castiel always made for Dean would not be heard thanks to Sam's ministrations. Castiel would end up on his back with Sam hovering and Dean behind him. Dean's fingers would ease into Sam's ass, spreading and stretching. All the while, Sam would do everything he could to work Castiel into a frenzy. After orgasms all around, there would be soft kisses and sighs of contentment. Sam would be so happy. So, so is afraid of what would happen if he allowed himself to sleep and dream. Would he scream Dean's name? Or Castiel's? Sam can't allow himself to find out.

One morning, Castiel asks about the circles under Sam's eyes, but Sam brushes him off. Castiel can't really care. He's only asking because he cares about Dean, who cares about Sam.

Sam does everything he can to stay away from them. He makes excuses to leave them alone. It gets to the point where he's spending more time alone than not. The only solid time he's around Dean, Castiel, or both is when they're in the car. He doesn't even stay at the motel at night. Sam doesn't see the need to if he's not sleeping anyways. He usually sits in the car, but he might go to a bar if he feels like drowning his sorrows in alcohol.

Food loses its taste, colors become dimmer, books become duller, Dean's jokes aren't as funny, and music loses its luster. Overall, Sam would rather be by himself. Most of the time, he finds a way to be alone and sits in complete silence.

It's a Tuesday when Sam is walking back to the motel. It's the first time he will be spending actual time with Dean and Castiel in about four months, but Sam wants to see them for awhile, especially with what he has planned. He's sorted out his thoughts by the time he reaches the door to the motel room, but he hears movement from the inside of the room. It's the unmistakable sounds of hot, passionate sex. Sam closes his eyes.

Part of Sam thought Dean missed having his little brother around him. The pleasurable screams inside the room beg to differ though. Dean seems to be just fine without Sam around. He gets more time with Castiel. He doesn't have to worry about his troublesome, little brother. Dean would be better off when Sam's not around anymore. A depressing thought.

Sam turns away from the door, deciding to go get a salad from the nearby diner. He has to make plans. He knows what he needs to do.