Title: Love at First Sin

Rated: M

Summary: AU. Looking to blow off some steam, Dean finds a nameless, beautiful man that completely rocks his world, more than just physically. Imagine his surprise when the very man shows up at family brunch... holding Sam's hand. Beginning Sastiel, with Destiel and eventual Sabriel.

A/N: After rewatching episode 200 and hearing Sam say, "Sastiel? Samstiel?" I thought about it and realized that they (as normal non-hunter non-angel men) would make a plausible couple. Of course, not as passionate as Cas and Dean, but hey! That's what fan fiction is for! Here's to exploring if opposites really do attract.

This is sort of... experimental for me. I haven't written much of this, but I'm going to post the first chapter to force myself to finish it. I'm almost done with my other fic, The Raven, but as the almighty Chuck says, "Endings are hard." Enjoy!

Love at First Sin

Chapter One

It had been a bad day for Dean Winchester.

Bobby would never admit it, but he loved Sunday brunch. He, Sam, Dean, Ellen, and Jo would gather at the dusty old house and have a sit-down meal. Ellen told everyone that that the only reason they could ever miss brunch was if they were dead and buried. So Dean went to brunch.

It started off as all the others did. Bobby and Ellen skirted around each other in the kitchen, exchanging small smiles and little "Oh, let me help you!"s. Dean gathered the silverware, shaking his head. The two of them should just admit their feelings and get it on already. The older Winchester gagged a little when a mental picture of that came to mind.

Jo lay on the couch, moaning. She had some sort of stomach virus, but the doctor said she was no longer contagious after three days of antibiotics. Still, she looked pale and in pain.

"Jo," Dean squatted down next to his adoptive sister. "You need to go upstairs and sleep. You sound like you're dying."

"Don't mother hen me, Dean," she groaned, sitting up. "I get enough of that from my own mom."

Dean chuckled and ruffled her blonde hair, earning a sound of annoyance. "You're at least going to take some painkillers, don't argue. You know I'll force-feed you if I have to." Jo rolled her eyes and slumped back onto the cushions, but swallowed the pills dutifully.

It was when Sam got there that things took a downward turn.

"Hey Sammy," Dean called from the kitchen. Sam didn't even respond. Instead he stomped right into the living room and threw himself on a chair.

"What's got your panties in a twist?" Jo croaked.

"It's nothing," Sam stared resolutely out the window.

"That's the weakest lie I've ever heard," Bobby stood against the doorframe. "What's eatin' you, son?"

"I don't want to talk about it," he mumbled.

"Lemme guess, someone deleted all the documentaries off your DVR?" Dean joked, trying to lighten the situation. Sam never liked getting attention when he was upset. "Food's ready, by the way."

No one moved. They crowded Sam, and Dean knew that it was only going to make his mood worse.

"What, do I need an audience for my pain now?" Sam stood and pushed past Bobby, storming off into the junk yard.

Dean tossed the kitchen towel onto the table and sighed. "I got it," he motioned for everyone to go ahead and start eating.

Sam was pacing in front of a beat up Toyota when Dean got to him. Sam was just itching for a fight, and Dean wasn't in the mood to take it. Some yelling occurred, and Sam punched a car. Better than punching him, Dean supposed, but Sam was ungodly strong and managed to break off bits of the frame into his skin.

They went to the emergency room.

Sam broke two metacarpals and had six pieces of metal removed from his knuckles. Ellen worried over him, switching between protective and scolding the entire time. Jo stayed at home with Bobby, who should have come with them. Dean stayed with Sam, talking quietly to the doctors and nurses.

After a while, Dean told Ellen to please go wait in the waiting room because he needed to talk to Sam.

"Seriously, man, what's wrong? You can't escape in here, and you can't punch anything." Dean sat down, giving Sam the I-don't-do-feelings-but-I-love-you-so-talk-to-me-dammit look.

Sam rubbed his eyes with his unbroken hand. "It's my boyfriend. We had a big fight last night."

Sam had always had really bad luck with relationships. Over the years, that made him paranoid, clingy, and suspicious, which put him in an even worse mindset for dating. But Sammy loved love, and it never stopped. This particular boyfriend that Dean rarely heard about had been around for two months and had never met the family. He honestly knew nothing about him, other than the fact that his name was Castiel.

"What about?" Dean asked carefully.

"He's been distant lately." Sam closed his eyes. "He'll just up and leave for 'me time' without any warning. I don't want it to end, Dean." Sam's lip started to quiver and Dean was immediately at his side.

"Hey, if this guy doesn't see what's right in front of him, it's his loss," Dean rubbed Sam's shoulder. He knew the 'I'm sure they love you' route was the wrong way to go about comforting Sam, because these kind of relationship problems with him usually lead to breakups, and Sam was always better about it if he was prepared for the end to come.

"I mean it, Sammy. Don't settle just because you don't believe you can do better."

Sam snorted. "This coming from Mr. Emotional Competence." The jab didn't sting anymore; Dean was even worse than Sam when it came to relationships, and he had given up on them a long time ago.

"Come on," Dean changed the subject, pulling Sam out of his chair. "Let's go back to the house. I'll put extra blueberries on your pancakes."

After the somewhat tense late-brunch, Dean put in a shift at the garage. He hated working on the new models of sports cars. He was a classics kind of guy. But new sports cars broke down and their owners paid good money, so he spent the afternoon under the hood of a Jaguar trying to piece together what made this weird engine spontaneously die three days in a row.

His working went nowhere, and soon the sun was setting and he needed a drink. Shower, microwaved pizza, hit the road.

Usually Dean would hit up the Roadhouse, but he wasn't in the mood for Ellen to grill him about Sam. The next best choice was Lafitte's, a local bar that was the perfect mixture of classy and seedy.

"Whiskey. Uh, double," Dean told the bartender. He swallowed half the drink at once, the burn comforting in the cold room. Maybe he needed to take someone home. His dry spell was going on two months now, and that was incredibly unacceptable in his books. He'd just been so tired.

Dean sipped at the rest of his whiskey, surveying the room for any willing women. Or men. He was an equal opportunity kind of guy, though he preferred men. They were just harder to come by. There was a pretty redhead in a group of girls eyeing him from across the room, and two blondes at the end of the bar whispering and giving him the occasional shy glance.

Dean turned and spotted a man at the other end of the bar, alone. He licked his lips. This man was absolutely gorgeous. His suit was a bit rumpled, but the electric blue tie he wore matched the intense blue of his eyes. His messy black hair stuck up perfectly, and a strong jaw moved under scruffy skin as he sipped his drink. He looked almost elegant, with a touch of innocence.

The man looked up and caught Dean's eye. This would be the telling moment. Did he like what he saw? Did he want Dean to come talk to him? Dean suddenly wished he was wearing something nicer than his ripped up jeans and leather jacket.

That didn't seem to matter to the man, who gave Dean a little flirtatious smile. Yahtzee.

Dean returned the smile and slid off the barstool. The man held eye contact until Dean was right there next to him.

"Let's hear it," he said. Dean stopped, partially confused by his words and partially stunned by his amazing voice. It was low and growly and would probably sound even better in bed.

Dean cleared his throat. "Hear what?"

The man smiled. "The cheesy one-liner you're about to give me."

Dean's grin returned and he slid into the seat next to the man. "Do I look like a cheesy one-liners kind of guy?"

The man's eyes glided down his body and back up, shamelessly checking Dean out. "Hmm. The leather jacket and devil-may-care look in your eyes says you're a ladies man, but you're talking to me. Equal opportunity, I presume?"

Dean laughed. "Spot on."

The man turned to face Dean completely. "So what do you usually say to your potential conquests to get them to go home with you?" The words held no malice or judgement, just curiosity with a bit of humor in them.

Dean quirked an eyebrow. "Well, ordinarily the cheesy one-liners work. But for you..." Dean looked this man up and down. His suit wasn't very tight, so he wasn't wearing it specifically to attract people. There were little crease lines in it, so he had probably worked or done something today. There were very faint dark circles under his eyes, and he was sitting at the end of the bar, partially hidden from view. This man didn't come here to get laid. He came here to drink. On a Sunday.

"I'm going to buy you a drink and ask you what's wrong."

The blue-eyed man's lips parted in surprise. "I... uh..."

Dean motioned to the bartender to get another drink for this man. "You don't have to tell me if you don't want to, but sometimes it's easiest to talk about stuff with a stranger." Dean leaned back and gave him an honest, open look.

"Well," the man fiddled with the hem of his suit jacket. "I'm having some family trouble." Dean raised an eyebrow and stayed quiet. The man sighed. "Two of my brothers are fighting over the inheritance my father left us. He died recently."

Dean immediately felt terrible. This guy was not looking to get laid at all. "I'm so sorry," Dean mumbled.

"I don't know why people say sorry," the man chuckled humorlessly, downing the rest of his first drink. "It's not your fault."

Dean's brow creased. "I guess I'm using the word as an adjective. I'm filled with sorrow at your loss. I'm sorry." Dean traced the rim of his glass. "I get it, actually. My dad died a few years ago. It's a hard thing to go through."

The man looked at him, and Dean couldn't really decipher the look. He prided himself on being able to read people, but that look... "It's a trying situation."

"Are you all okay? Like the rest of your family?" Dean asked. He remembered the toll John's death took on him and Sam.

"My mother is dead as well," the man said matter-of-factly. Dean's eyes widened. "I mean, it was a long time ago. I was two. Don't say you're sorry again." Dean shut his mouth and nodded, and the man smiled. "It's changed the dynamic of my family. All I have left are my brothers and sister, and most of them seem pretty unaffected."

Before Dean knew it was happening, his hand slid across the bar and covered the other man's. He didn't say anything. What was there to say about that?

It was if the touch woke the man up. "God, I'm sorry for unloading all my problems on you." He didn't pull his fingers away when Dean traced his thumb down the skin.

"Nah, it's fine," Dean said. "Like I said, unloading on a willing stranger helps sometimes."

The man straightened up. "Your turn. Something's bothering you too."

Dean chuckled and looked down at their hands. "I guess..." he trailed off. "I guess it's just all the little stuff is getting to me. Life isn't as exciting as it used to be, you know?" Dean sighed. "I'm too young to be having a mid-life crisis. I'm not even thirty, for gods sake. I..." Dean pulled at the collar of his t-shirt. The room was suddenly stifling. "Do you want to go for a walk?"

The man looked wary now. "What do you mean, 'a walk'?"

Dean smiled. "Just a walk. Nothing you don't want to do. I want to get out of this bar, but I don't want to stop talking to you." He threw some bills on the bar and the man grinned broadly.

"I know a pretty nice place to talk. I'll show you."

They walked for almost twenty minutes, talking about menial little things. Dean liked bands like AC/DC and Metallica, and the other man liked Simon and Garfunkel and the Beatles. They would both cut off their arms for a good bacon cheeseburger. Dean was a mechanic, and the other man was an art museum curator.

They didn't exchange names. They had been talking for over an hour, and it seemed wrong to break this anonymous closeness of theirs. The man seemed to be on the same page as Dean, because he said nothing about it.

Dean was getting a lot of that- understanding what this guy was trying to tell him without so many words. It was a strange sort of connection, and Dean was walking the tightrope between casual interest and developing actual emotions for this guy.

"Hey, this is my apartment building," Dean said as they arrived at his place of residence.

The man looked surprised. "I didn't know that," he said honestly. "One of my cousins lives in this building, and the rooftop is a really nice place to simply be."

Dean grinned at him. His speech patterns were strange sometimes, and it was sort of endearing. "Lead the way," Dean swept an arm out in front of him.

The two sat against the side of the roof, looking up at the stars. They were quiet for a while, just enjoying each other's presence.

"Sometimes I wish I could fly," the man broke the silence quietly. "It would be amazing to see things above. Focus on the big picture rather than the details. I think it would make everything a little more beautiful. Make it worth doing all the things in life that you don't want to do, but you know you have to." His face flushed in the moonlight. "I'm not making any sense, am I?"

"You are," Dean assured him. "I kind of wish I could teleport. It sounds childish, I know, but think about it. You could go anywhere and do anything. You could see the world without cutting ties to the things- people- you have at home. You could... I don't know. Really experience stuff. Turn a black and white life into something colorful."

Dean looked at this other man and his breath caught in his throat. He was looking at Dean with wonder, like Dean was a beautiful landscape he'd never seen before. Dean was sure his eyes reflected that look. This man was something else, someone he didn't think was possible.

Dean didn't know who moved first, but the next moment his mouth was on the man's, lips pressed firmly against soft skin. His hands scrambled for purchase on the other man, one fisting his trenchcoat and the other gripping the locks of dark hair. The man made a little happy noise as Dean's tongue slid against his.

This kiss was something else. Dean was on fire, every place he touched erupted in tingles.

He needed to be closer, closer. Ha maneuvered the man onto his lap and pressed up against him, humming happily when he arched into him.

The man broke away for a second, pupils blown out. "Didn't you say this was your apartment building?" his voice sounded wrecked already.

"Fuck yeah," Dean choked, hauling the man to his feet and dragging them back inside.

They managed to get to Dean's door with minimal bumps and bruises; Dean couldn't help but push the man against the wall and attach his lips every minute or so. As soon as the apartment door slammed behind him, Dean nearly ripped the man's trenchcoat off and picked him up. The man's legs wrapped around him and he pulled at Dean's hair, angling his head for better access to his mouth.

This man was all fire and passion, nipping at Dean's lips and kneading his shoulders. Dean gave it all back, squeezing him roughly through the material of his suit jacket. His clothes were still on. That was unacceptable.

The man was on the same wavelength as Dean. He scrambled down from Dean's embrace and pushed his jacket off, along with Dean's leather one. Dean pulled at the buttons of the man's shirt, uncaring that a few popped off the fabric. The man shoved Dean's shirt up until Dean had to let go in order to pull the offending garment off.

They were both completely bare and on the bed. This was going so fast, but Dean couldn't restrain himself. The man was under him, and he bit down on the skin connecting the man's shoulder to his neck. The man moaned and rutted up against Dean, who ground down against him in turn.

"I want-" the man choked out.

"Yes," Dean answered. He made his way down the man's chest, pausing to lick at the pink nipples. The man arched up into the touch, so responsive. Dean was so hard it was painful, but he needed to taste this man even more than he needed his own release.

Without preamble, he swallowed the man's length down as far as he could. It was heavy and hot on his tongue and Dean sucked, greedy. The man gasped and scratched at Dean's back.

Dean withdrew his mouth after less than a minute and moved downwards, tasting every inch of skin he came across. He hadn't done this particular thing many times, but he wanted to so badly. He gripped the other man's thighs and pushed them upwards, exposing his beautiful puckered entrance. After one moment of appreciation, he leaned in and licked a slow line over the pink skin.

The man let out a yelp and bucked up into Dean's face. Apparently he hadn't done this much either, or at all. He whimpered, pushing his ass towards Dean's face as if asking for more.

Dean traced the circle of puckered skin, his tongue putting more and more pressure on it until he delved inside. The mewls and whimpers above Dean fueled his fire, and he licked and nipped and sucked until the other man was babbling.

"Top drawer," he muttered against the blue-eyed man's thigh. He struggled to comply as Dean continued his ministrations.

The man nearly threw the small bottle of lube and condom at Dean. "Ungh, please," he begged.

Dean complied immediately, slicking up a finger and pressing it slowly into the whimpering man below him. He accepted it with an eager "Aaah!" and pushed down onto Dean's finger. Dean added another, perhaps too quickly, but the man just gripped the sheets tighter. "More, please," he gasped.

Dean probed deeper and crooked his fingers, looking for that magic place inside him. The man nearly sobbed beneath him. Dean added another finger and hit his prostate with every stroke. "Please, I need you now, please," the man begged.

The condom was on and Dean was slicked up in record time. Only then did Dean stop and look at this gorgeous man beneath him.

There was barely any blue left in his eyes, swallowed by hungry pupils. His lips were red and raw and sweat glistened on his skin. The lean muscles of his arms and torso were flexing and relaxing, as if searching for a purpose. He was shaking with need, staring at Dean like he was trying to read his soul. "Please," he whispered.

Dean felt himself nod. He draped himself over the man and kissed him like he was drowning. As slowly as he could manage, he sheathed himself into the man's tight heat. "Fuck," he whispered, breaking the kiss.

The man's eyes widened and sucked in a breath. Dean bottomed out and sat there for a moment. "Ahh, breathe, sweetheart," he commanded, and the man took several shuddering breaths.

Dean kissed and nipped at his neck until he heard, "God, please move!" Dean withdrew and pushed in again, this time harder, testing this man's tolerance. "More," he whimpered. Dean thrusted harder and the man took it eagerly. "More!" Dean slammed into him and the man sobbed in pleasure, bucking up simultaneously.

"Jesus," Dean growled, pounding into the man for all he was worth. He felt amazing. Dean's vision was tunneling and his entire body was on fire, bolts of electricity shooting up his spine with every thrust.

The man under his was resilient. He had one arm wrapped around Dean's neck and one gripping his bicep with surprising force, nails digging in. His legs were wrapped around Dean's waist and he was babbling "more" and "please" and "yes" and nonsense syllables.

Dean was grunting into his neck. He knew he wasn't going to last long. He shifted the man's hips up and snaked a hand between them, gripping his diamond hard member. Dean stroked once, twice, and then the man was screaming his release. He clamped down hard on Dean, and with one more thrust, Dean was flying, waves of pleasure sweeping over him.

He managed to roll when he collapsed and landed next to the panting man with a hum of satisfaction. After his heart rate was down into the safe zone, he grabbed his t-shirt and wiped the mess off the blue-eyed man, who chuckled.

This was the part where Dean would usually get dressed and tell the lucky man or woman thanks, give them cab money if they needed it. He glanced at the man across from him. Those big blue eyes were giving him that same look from the rooftop, that look of awe and something else. He bit his lip, and Dean was done for.

He scooted towards the man and pulled the covers over both of them. Dean gathered the pliant body into his arms and arranged the man so he'd be comfortable. The man smiled up at him, a sweet, secretive smile, and pulled Dean's face down for a kiss. This one was soft and languid and said different things than the mind-blowing sex. It was gentle and comforting and something else. It felt like the kiss Dean received the first time he ever said "I love you" to a girl.

That fact alone should have terrified him. But the man nuzzled into his neck and promptly fell asleep, and Dean couldn't help the big stupid grin that spread across his face. He'd be terrified later. Now, he would sleep.

Dean woke slowly, another body stretching against his. It was the man from last night. That wasn't just a dream.

He stretched his own heavy limbs. "Morning," he mumbled, kissing the man's scruffy cheek.

"Mmm," the man hummed. "Morning." His eyes blinked open, suddenly alert. "Monday morning." He glanced at Dean's bedside clock, which read 8:40. "Shit," he growled, flinging the comforter off himself.

"What, what's wrong?" Dean shook his head, trying to wake himself up.

"I'm late for work!" the man scrambled for his clothes, pulling them on hurriedly.

Dean knew he couldn't really do much, so he stumbled into the kitchen, naked, and pulled out a granola bar and a styrofoam cup and a lid. Thank god his coffee pot was set to brew at 8:30.

The man ran out of his room in time to see Dean, still very naked, holding coffee and a granola bar with a lazy smile.

The man groaned in appreciation of the sight and pulled him into a deep kiss. It lasted maybe three seconds, but it still made Dean warm and tingly. He took the granola bar and coffee and kissed him once more, softly.

"Goodbye," he whispered against Dean's lips. And then he was gone.

Dean's door closed and he brushed a finger over his lips. Fuck.