Summary:

Dean knew he shouldn't. He didn't even know the kid's fucking name - but all he wanted was that taut little body on the end of his cock.

(Originally written for a prompt on livejournal: "Cas (18 to early twenties) and Dean (in his late 30s) doing the do. I would like emphasis on the difference in size and age between them, and Castiel accidentally calling Dean "daddy")

Rating: NC-17
Pairing: Dean/Cas
Warnings/Tags: Daddy Kink, Alternate Universe - Not Hunters, Size Difference, Age Difference, Twink Castiel, Barely Legal
Word Count: 3668
Notes: Hope you enjoy! Kudos and comments and all that wonderful stuff are most welcome! ^_^

That fucking kid was back again.

Dean got a lot of this type down at Singer's – teenagers wanting to fix up their shitty cars, make the engines as loud as possible in order to try and convince the rest of the word that they owned a real racer when it was actually just a crappy tin can on wheels that made a lot of noise. But this kid was… different.

He looked barely a stroke over eighteen, which made Dean's thoughts about him even more inappropriate. Thirty-eight year-old men were not supposed to obsess over barely-legal teenagers – but Dean was willing to bet his fucking Impala that anybody who said they didn't find the kid attractive was outright lying, straight or not.

He was a lithe little slip of a thing, taut muscles not overly-huge like some of the other knuckleheads that hung around the autoshop - with high cheekbones and pale skin, a light dusting of stubble that would feel fucking electrifying on Dean's lips. And underneath his unruly mop of thick black hair were his eyes. Fuck, his eyes – they were these deep, wide baby blues that looked so damn innocent, like he was just begging to be put to good use on the end of Dean's cock. All the mechanic could ever think about when he jerked off in the shower was that blue gaze looking up at him, plush lips wrapped around his dick, bobbing up and down. That kid had cocksucker lips alright. He was sure he had only been created to get Dean arrested.

Hell, he didn't even know the kid's name – all he knew was that he was jailbait and that Dean was screwed.

Especially now, since the kid was fucking walking up to him.

"Dean Winchester?" and oh shit, Dean could deal with the good looks and the cocksucker lips and everything, but that fucking voice? What the hell? Why was he here, tormenting Dean at seven in the evening?

"That's me," he answered, thanking whatever God was listening that his lower half was hidden by the hood of an old '55 Chevy Bel Air he was fixing up for Bobby – because he was currently sporting a hard-on to rock the ages.

Yep. Looked like he was going to the special Hell.

"You're the main mechanic here, right?" he asked, and Dean would be lying if he'd said he wasn't following every movement of the kid's lips as he spoke, heat licking up his insides.

"When Singer's not here, yeah," he nodded, blood pumping when the teenager beckoned for him to follow as he walked away, ass, round and so damn firm in his jeans that Dean was sure he'd be able to bounce a fucking nickel off of the damn thing. God, he'd sell his fucking soul to feel that around his cock.

The kid led him to the other side of the garage (Dean was still adjusting to the size of the place, ever since Bobby had bought it), stopping by a cherry red Mustang with its hood flung open. The kid was peering into the engine, crouched over, ass flung up into the air and it took every shred of self-restraint Dean had not to reach out and grope it through the denim. The kid straightened, smiling when Dean joined him by the car, and the mechanic found the fact that the teenager was a good four inches shorter and much less broad in the shoulders than him that much more arousing.

"I was wondering," he began conversationally, as if he were discussing the weather rather than turning Dean on, "If you could help me replace the carburettor. Oh – I'm Castiel, by the way."

Castiel – the name fitted to a 'T'. Dean wasn't a religious nut but his brother had gone through a phase when they were younger, all that praying and Bible thumping shit – Dean knew enough angel names to know when he heard one. It just increased the 'inappropriate' level to the max. The lithe, barely legal teenager with the big blue innocent eyes and an angel name. Fuck, Dean was so totally doomed.

Dean, remembering he, hello, was a mechanic and supposed to be doing his job, ducked his head to take a look at the engine, grinning when he saw it was completely pristine, bar the carburettor that looked at least five years old, dull and dusty. He glanced at Castiel, trying to focus on the job rather than the jailbait stood before him.

"Should be easy enough," he reassured, relishing the way those plush lips tipped up into a grin, "I just gotta get my toolkit – back in a sec."

Dean didn't think he'd ever moved so quickly. His body really could be very persuasive, sometimes.

Soon, he was bent over the engine, tools balanced precariously on the lip of the hood, working the carburettor out of its place, trying desperately to ignore the persistent, painfully obvious presence of Castiel stood beside him, watching his every move. His heart was beating rapidly, pounding so loudly against his ribs that he was surprised the kid couldn't hear it. Castiel's hip actually nudged Dean's at one point, and Dean jerked so violently that his elbow knocked a spanner to the floor with a loud clank.

"Shit, sorry –" he began, standing to retrieve the treacherous thing, but Castiel beat him to it, crouching down onto his knees and oh fuck, here came the inappropriate thoughts.

Castiel grabbed the spanner, looking back up at Dean and shit, there was a shower fantasy right there – Castiel, on his knees, face level with Dean's crotch and – crap, oh crap. If Cas hadn't noticed the bulge in Dean's jeans before then there was no way in Hell that he'd miss it now.

Dean would've preferred to dance in hellfire than watch as Castiel eyed his boner, spanner still in hand, cocksucker lips falling agape in a minute gasp of surprise.

"…Uh," Dean murmured uselessly, because what else could he fucking do? He was this fucking close to running away and shoving his head in the nearest pile of sand he could find. He wanted to die, wanted the ground to swallow him up whole, right there and right then, even when Cas' hands snaked up to rest on his thighs and – wait, wait one motherfucking second, Cas' hands were on his thighs?

When did this happen.

Those baby blues blinked lazily up at him, head tilting as those lips pulled into a slight pout.

"…Want me to take care of that, Dean?" He asked lightly, ghost of a smirk on his lips, and oh fuck, oh fuck oh fuck – the moral implications could go screw themselves. Dean was gonna grab himself a handful of twink ass tonight and he was gonna fucking enjoy it.

He reached down to grasp Cas' stubbled chin, pulling the teenager up to meet his lips and shit, nothing he'd ever imagined had felt this good – Cas' plump lips were soft against his, mirroring every hot slide of skin with ease, tongue swiping across Dean's bottom lip and then the kid actually fucking moaned into Dean's mouth, elegant hand running down the mechanic's chest and letting fingertips run across the sliver of skin beneath Dean's t-shirt. Cas was a fucking energetic kisser, all bouncy and enthusiastic and Dean fucking loved it – he reached down to grip the teen's narrow hips, pushing him back against the Mustang, shoving a leg between his thighs, his own cock throbbing when he felt the hard line of Castiel's dick against his thigh.

"Fucking driving me crazy, Cas," he growled into Castiel's neck, loving the way the teenager rutted shamelessly against his thigh, needy little whines sounding in the back of his throat, "So fucking hot –"

"Dean…" Cas exhaled shakily, whole body jolting as Dean sucked an angry mark onto the smooth 'v' of the teen's jugular, "Want you – want you to fuck me so bad –"

Dean buried his head into Cas' shoulder, groaning out his appreciation – oh, he'd fuck him alright. Fuck him until his eyes rolled and he was crying out. He'd mark that firm ass up – ruin it for anybody else. He was gonna make sure of it.

"There's a - fuck, Cas – private room, out back –" He didn't even need to finish the sentence; Cas was already tugging him away, and Dean was silently praying out his thanks to whomever had decided to answer his prayers tonight.

The private room was used by Dean, mainly. Usually after he'd been working for twelve hours straight, sometimes fifteen – in it, there was a single bed, a nightstand, and a water cooler. The last two meant nothing to Dean, as he was currently lip-locked with the jailbait he'd promise he'd never go near, so hard he was surprised he wasn't going dizzy. Go figure.

Cas slammed the door shut behind them and Dean pulled him over to the bed, yanking his t-shirt clean over his head and making light work of Cas' too – and fuck, Dean had been completely right about the boy. Pale, lean muscles, slender and so small pressed against Dean's own, more bulky exterior. The feel of it – of Cas' wiry frame, tight and scorching against his own was too damn good for words. Dean was mesmerised by this chaotic fireball in his arms.

Cas settled on Dean's lap, arms snaking around the mechanic's neck as his hips rolled, clothed cock sliding against Dean's as he ran his hands up the smooth expanse of milky-white shoulder blades, before trailing back down again, fingertips dipping into the dimples pooling at the teen's lower back before going further, squeezing Cas' ass through the denim. Cas mewled, squirming in Dean's lap as he panted into the mechanic's mouth, digits curling in the short hair at the back of Dean's head.

"Please," he begged, hips jerking erratically as he clutched Dean closer, "Please Dean…"

"In a minute, baby, I promise," he gruffed, eyes clashing with Cas' own pleading ones, "Gonna make you feel so fucking good…"

Cas tipped his head back, a long, low growl ripping itself from his flushed throat and Dean took the opportunity immediately, peppering the pink skin with tiny nicks of teeth and small lines of kisses, following the line of the teen's jaw, melting at the feel of the stubble beneath his lips. His hands were working feverishly on Cas' jeans, undoing the catch and sliding the rough material down the teen's thighs – he could've laughed at how eagerly Cas stood in order to get the offending garment off of his legs. 'Could've' being the main word there – his laugh died in his throat when he looked down and realised the kid had gone fucking commando.

"Just for you," Cas breathed, eyes alight and wild, cock flushed red with need as it hung between his legs, "Wanted you since I first walked in."

Dean could only gape as Cas fell to his knees, pushing Dean's legs apart as his hands slid up to toy with the zipper on his jeans – Dean reached down to undo it, but Cas batted his hands away. Rather than using his fingers, Cas knelt up, and Dean had to thank years of practice for not coming right then as the teen undid the zipper with his teeth.

"Fucking hell, Cas…" Dean groaned, the pressure lessening slightly on his cock as Cas began to drag both jeans and boxers down, "How long have you been planning this?"

Cas shrugged, tugging the mechanic's last items of clothing off completely, and Dean shivered when the cool room air wrapped around his cock, precum already pearling at the tip. Cas' eyes widened.

"Jesus Christ, you're pretty fucking cut…"

The teen was eyeing the full, thick length of Dean's cock hungrily. All nine inches of it. Dean almost felt like shying away. He knew he was well above average, no question – but the way Cas was staring at his cock like it was the meaning of life was a bit unnerving. That is, until the teen was gripping the base and sinking his mouth down over it in one long torturous slide. Dean groaned lowly.

It was hot – blazingly hot, slick and wet and tight and Dean couldn't help but buck upwards a few times, visceral, watching avidly as those spit-slick lips smirked around his cock, kissed red and stretched gloriously wide. Cas gagged a little as the head hit the back of his throat, but he didn't seem to care all that much. Dean's hands tangled in his hair – a thing he'd only thought he'd envision himself doing – tugging the teen's head back and forth, the searing friction making white spear across his vision.

"Fuck Cas, right there – " Cas' tongue swirled around the head, before he bobbed his head back down and drew a yelp from Dean's chest, "Oh fuck…"

Slim hands were rubbing up the sensitive inner sides of his thighs, fingernails tracing the hot curve of his hips, leaving him writhing and bucking beneath Cas' mouth, hold like iron amidst Cas' hair – he wanted to go gentle, he really fucking did, but this teenager was doing things to him, making heat smother every inch of his skin and causing the hairs on the back of his neck to stand up, toes curling into the floor. It was too fucking good to be true – to have this lean creature knelt between his legs like an obedient little cocksucker, taking everything Dean had and more, head bobbing up and down, over and over –

He yanked Cas' head away, mouth pulling off of Dean's cock with an obscene pop. Dean was left trembling, orgasm just seconds away – as much as he'd love to paint the teenager's face with his come (what a mental image that was) he didn't want it to end just yet. He wanted to have Cas beneath him, begging to come as Dean fucked into him, round ass bouncing as Dean's hips snapped ruthlessly before it ended. Yeah. Dean'd like that.

"Gonna make me fucking come," he laughed weakly, massaging Cas' scalp with soothing fingers – the teen blinked up at him, eyes nearly completely black with lust. He tugged Cas' hair gently, coaxing him onto the bed, making him balance on his hands and knees whilst Dean reached for the bedside drawer, inwardly cheering when he found some lube he'd left there weeks ago. Maybe it'd been some kind of subconscious impulse to prepare him for this. Whatever it was, Dean was grateful he'd done it.

Dean left the jar on the nightstand, settling behind Cas, running his hands up either side of the teen's spine, hunger flaring when he saw the other tremble, his slight form shaking with every ragged breath. Dean bent over double, tongue dipping into those little dimples and Cas actually fucking rocked back, too damn eager for Dean to handle. When Dean reached up to grab two handfuls of that glorious ass, Cas lost it, quivering and muttering incoherent babble. It was only when Dean let his tongue slip further, down and over Cas' entrance, did Dean get a truly awesome reaction.

"Oh fuck, Daddy yes!"

Cas stilled, getting a hold of himself whilst Dean froze behind him, tongue still flattened over the teen's puckered hole.

"…Shit, sorry, I didn't mean –"

"Fuck, that's hot," Dean cut the teen off, wet mouth pressing deeper between Cas' cheeks as his jaw worked open the teen's entrance – he pulled back a second later, Cas' hips grinding up into nothing but air, "…Say it again."

He waited, ears pricked for that – that word again. 'Daddy'… Fuck, his cock throbbed just thinking about it. He had to reach down and grip himself in order to stop himself from coming all over the backs of Cas' thighs.

"Please… Daddy."

Dean swore, making a desperate grab for the lube – 'cause he didn't think he could survive much longer. This walking pile of liquid sex was doing things to his libido; Dean might wreck Cas for anybody else, but Cas was absolutely ruining Dean's stamina. Something that had taken years to build up and one little fucking twink had ploughed a bulldozer right through it.

He'd slicked himself up in record time, sliding one slippery finger into Cas entrance, watching as the teen's arms gave out completely, head pressed into the mattress as Dean worked him open.

"Fuck, Dean, more –" Dean slid in another finger and Cas' back arched, crying out as Dean's fingertips brushed his prostate. His cock twitched, hard and neglected between his thighs – Cas all desperate like that was the hottest fucking thing Dean had ever seen. Screw pornstars, this was where the money was at. Cas' every muscle was coiled, shoulders solid and tense, clenching greedily around Dean's fingers, both pulling him in and pushing him out in equal measure. Dean couldn't take much more of this. In fact, after the third finger, he decided to throw patience to the wind.

"Roll over and sit up," he ordered, surprised at how quickly the teen obeyed, and fuck, Cas looked even better now than he had earlier. His hair was even messier, if that was possible, his throat and chest flushed as he drew in shallow huffs of vital oxygen, leaning back on his hands with his legs spread, cock hard and slick between his legs. The juts of his slim hips made the mechanic's thumbs twitch. Youth was evident on his person, barely any hair on his legs and no laugh lines around his eyes – just soft skin and sharp angles. Dean felt all hot just looking.

He sat back, legs dangling over the edge of the bed as he beckoned for Cas to join.

"I want you to slide on my cock, Cas," he said roughly, relishing the way Cas' eyes widened, mouth falling slack, "Fuck yourself until you come – would you like that?"

Dean had never seen anyone move so damn fast, a blur of pale skin and messy hair, and then Cas was sinking down onto his length, gasping and whining, heat tight and scorching and Dean nearly leapt off of the fucking bed, pinpricks of pleasure jolting across his every nerve as the teen split himself wide on Dean's cock. He was still so young - still so tight that Dean felt like he was breaking him. Cas' skinny legs actually spasmed, whole body tightening like a bowstring string as he sank down all the way, and that was when Dean was hit by a very sudden burst of inspiration.

Cas was so damn small in comparison to Dean that his lean weight barely registered on the mechanic's lap, and Dean wanted to take full advantage of that fact in order to try out something he hadn't done in years - he quickly whispered for Cas to hold on, the teen obligingly doing as he was told, head dipping between his shoulders as he rolled back onto Dean's cock, arms looping across the muscled span of Dean's back.

Dean braced himself, thighs tensing, and then, he stood, the teen still seated fully on his cock as Dean reached around to grip that firm ass.

Both men groaned as the new position allowed Dean to slam in deeper, Cas' legs hooking high up around Dean's waist, flexible slim thing that he was, fucking himself wantonly on Dean's cock, slamming his ass down over and over again, their skin slapping together. Dean's biceps were burning as they pulled the teen up and down, but absolute pleasure was overriding every other sensation – flames were coursing through his blood, a tight ball of heat gathering in the pit of his stomach, encouraging him to fuck faster. Cas was pressing his lips desperately into Dean's, sloppy and uncoordinated as he rocked jaggedly, crying out on every thrust, every time Dean's huge cock hit that sweet spot inside. Dean's legs bowed, pushing himself further up into Cas' slick channel, their bodies damp with sweat, chests pressing together, and it took far too long for him to realise the hoarse voice calling out Cas' name was his own.

"F-fuck," Cas breathed, head lolling to rest on the skin where Dean's neck met his shoulder, "Oh shit, Dean – Dean I can't –"

"I know," Dean whispered huskily into Cas' ear, tracing the smooth ridge of Cas' collar bone with his mouth, "Touch yourself baby, I got you."

A hand unravelled from Dean's neck, Cas reaching down to stroke his cock, the teen making all these fevered little sounds, coaxing Dean to keep going, keep spearing into the teen whilst he held him close, feeling every jerk of Cas' muscles, every hitched breath and choked off word – Dean pounded into the teen that much harder, every sound fuelling each relentless snap of his hips.

Abruptly, Cas arched, mouth falling open.

"Daddy – oh fuck, Daddy -!"

Come splattered between them, Cas falling silent as he worked through his climax, clenching hard around Dean's cock, and Dean just kept going, fucking the teen to completion, his own orgasm speeding towards him at a hundred miles a minute. It hit him hard – so hard that his knees buckled and he had to fall back onto the bed, hips flexing, pushing as deep into Cas' willing little body as far as he could go, heels of his feet digging into the cheaply carpeted floor, the teen's name broken and ragged on his lips.

Come leaked down between Cas' thighs when Dean pulled out, wracking a shiver over the older man's body as he fell backwards, cradling Cas' head against his chest, running the damp strands of dark hair through his fingers as he came down.

"…Can we do this again?" Cas hummed sleepily against Dean's chest, fingers tracing patterns over the mechanic's chest. Dean bit his lip. No, they really, really shouldn't do this again. It was bad and wrong and went against everything Dean promised he wouldn't do and –

"Of course."

Damn.