I originally posted this on my tumblr, but I thought you all would like something.

Also,
this isn't the Supernatural fanfiction I mention on my profile. (Sam isn't even in that one, actually.)

-ooo-

"S-Sam," Castiel moaned, his hand reaching back to bury itself in long brown hair. The younger of the Winchesters was thrusting into him, eyes flashing black as he allowed himself to enjoy the carnal pleasure. His mouth pressed burning kisses to the angel's neck, accompanied by nips and sucks to decorate his skin with light, possessive bruises.

The angel of Thursday had not expected this, had not the slightest idea he would become this man's lover; but defiling an angel was apparently a viable replacement for gorging himself on demon blood. Dean had wanted his brother to stop and Castiel, after discovering this "stand-in," he had willingly given himself to Sam. It took no convincing for either of them, because if they were completely honest, it was all for Dean.

"Sam, I've almost…reached clima-ah." The angel's deep blue eyes fluttered closed as the human's cock was flush against his prostate. Sam growled against his skin, biting down roughly in an attempt to draw blood. It surfaced, but proved only to be as metallic as any mortal's. He growled again, his hips beginning to slam against the other man's hips violently in his disappointment.

"Coming for the second time?" Sam finally replied after he pulled away with a grimace, "Cas, you're really starting to like this." The angel was going to retort something about that being obvious, but his orgasm whelmed his capacity to speak, even flooding his head with a mind-blowing explosion of white heat.

"Tight," the mortal grunted. His hands gripped Castiel's hips and forced a few more thrusts into him before pulling out. He pumped himself, watching the higher being as his back continued to arch and his body trembled slightly with the force of his ecstasy.

"Cas."

"Y-yes, I know." He turned himself around, still unsteady, and dropped down to press a few kisses to Sam's hand. It pulled away from the weeping length, allowing the angel to descend his mouth onto the all-too-familiar cock.

As his head moved up to begin, the door to the motel room swung open.

"Hey Sammi, got us…dinner…" The bag of burgers was dropped to the floor as his green eyes widened in utter shock. It took him a moment for him to process the scene, and for the better part of that moment, Castiel kept his mouth on the younger Winchester's erection.

"What…the hell?"

"Dean, we can explain-"

"It's because of you," Castiel said once he sat up. This confused Dean even further, so the angel continued, "When we have sexual intercourse, Sam's hunger for demon blood is quenched. Apparently, making love to an angel suffices for his unorthodox hunger."

"And that's got shit to do with me because…?" He said this impatiently before finally picking the bag back up and slamming the door behind him. There was no need to let the whole world see this disturbing sight.

"I knew you wanted your brother to cease his… extracurricular activities, so I brought this to Sam and he was also aware of your distastes. So we started having-"

"You're doing this…to make me happy? You expect me to buy this crap?"

"Of course," the higher being replied, "Dean, we would do anything for you. I have done everything in my power to help you, to please you."

"And this is the best I can do. Do you want me to go back to-"

"No!"

"Then what's the problem? I mean, I know it's weird…and I really think I still don't…you know, swing that way, but…I don't know, it works." He ended with a shrug and a helpless look that calmed his older brother's anger to the point that he approached them.

"I don't want you doing the other thing, but this? And with Cas, of all the people…"

"What is wrong with me? I am a suitable lover, am I not Sam?" He looked to his lover with curious blue hues. Sam smiled gently, hardly remembering his rough, demonic side that had been in command only a few moments ago.

"Yeah. You're good, Cas."

"Thank you. So what is wrong with me, Dean?"

"Cas, it's not…"

"Is it because you're jealous?" the angel piped, causing his human's expression to grow into a sort of worry.

"What? No!"

"Dean, I can see your emotions. I can see your anger, your guilt…and your jealousy. You wish to…join us?" He wasn't sure if he had intended it as an offer or if he was accusing the man, but the next thing he knew, Dean Winchester had pressed their lips together and was peeling his leather jacket off.

"You tell anyone, I'll kill you both," he murmured against the angel's soft mouth. He bit at his lower lip, preventing him from speaking. He knew his friend too well, as Castiel had intended to retort that it was highly unlikely that Dean could kill him.

"Yeah, I'll tell everybody right after I tell them Cas is an angel and I've got demon blood in me," Sam snorted, trying to ignore the fact that watching his brother grind and strip against the angel was sending flames licking throughout his body. But it quickly proved to be too much. Before he could stop himself, as if he wanted to, he was kissing down his brother's spine.

"Whoa," Dean jerked back, obviously not accepting this position, "It is not going down like that."

"Sorry, I just…well, I'm not letting you do anything back-"

"I was under the impression that I would suffice for the both of you," Castiel interjected. The Winchesters looked to him; something dark crept across Sam's features while his brother frowned.

"Cas, you sure you can…you know, fit us?" The higher being gave a short nod, all too aware of the younger sibling's still unsated hunger.

"Remove your clothes and lay back, Dean," he commanded, though it was gentle in tone. The older hunter quickly did as he was told, but it didn't seem to be fast enough. Sam turned their angel guardian around and forced a kiss onto him.

"I can't hold it, Cas," he hissed as he worked his mouth against the familiar one.

"Soon," Castiel said, "Give me a moment, Sam." Instead, the longer-haired brunette pulled the angel close, grinding his body against him. The older creature moaned and whimpered slightly, his hands clinging to warm flesh instead of pushing away.

Perhaps he was beginning to enjoy this too much…

"Cas." The other's voice tore him away from Sam, blue eyes flicking over to a very naked - and very erect - Dean Winchester. The higher being crawled over to his side of the bed, stopping only when he was straddling the man's wide hips. He ground down against him, his own cock stirring back to life in response to the stimulus. Eyes closed, focus shifted, and then Castiel could feel the sudden slickness of lubricant in his rectum. One of the little-known perks of being an angel: it was much easier to prepare for anal sex with Heavenly powers, though it was certainly a misuse of such power.

"Wait, don't you need to-" Dean couldn't finish his sentence, his breath hitching slightly as his angelic friend dropped himself down onto the cock. It had taken only a second to guide the head of his erection into his puckered hole and being filled was a sensation he was beginning to acclimate to.

"Damn," the older Winchester groaned, hands sliding up Castiel's legs to his hips. He lifted him up and brought him back down, resulting in a shared moan. The angel began to ride him after that, finding himself lost in the sensation. This was different than what he shared with Sam. The way Dean's eyes scanned him over…He wanted to devour the angel, to taste every inch of him. But Sam's gazes had been searing, sometimes terrifying.

Unlike the necessity of his relationship with Sam, making love to the man he would do anything for felt absolutely clean, pure in a way that he couldn't quite pin down.

"Cas," Sam reminded. The higher being seemed to return from his thoughts. He paused in his movements, leaning forward so his chest was pressed to Dean's.

"Take me." Without hesitation, the younger sibling surged forward - attempted to, anyway. He grimaced at the almost uncomfortable tightness, making slow progress as he thrust forward. Though the angel wanted to cry out, he held his tongue. He made a pained face, however, that Dean caught a glimpse of.

"Tell us if you can't , Cas," Dean muttered, tugging his head closer until their lips met once more. They kissed sweetly, delicately, though it was short lived. Sam quickly acclimated to his position and began moving at a steadier pace. Of course, having already been near his orgasm, he immediately moved to a pounding that sent Castiel gasping for breath.

"Ah, S-Sam…Dean…" He panted out their names, desperate for something he could never quite name. But when the older Winchester managed an off-key thrusting with his brother, that was apparently what the angel had been wanting. Pre-cum pearled from the tip of his erection, smearing onto Dean's chest, but the hunter hardly seemed to care.

"Cas." Understanding the younger human, Castiel sat up with a dizzying expression so that he was in the more demonic sibling's reach. A mouth sank onto his still bleeding bite mark, though it was still only a trickle, and drank the plasma from him.

It wasn't nearly as satisfying as what Sam truly desired, but paired with their surely sinful act, it sated his carnal hunger. As he sucked and fucked, Sam found himself deliciously close to his climax and within a few thrusts, he came hard inside his lover.

The sensation of being filled to the brim and beyond was bound to send the higher being over the edge and spiraling into his own orgasm, and when it did he buried his mouth into the crook of Dean's neck, muffling the cry that his pleasure tore from his throat.

The younger Winchester pulled out of the angel, catching his lost breath. This gave Dean the opportunity to push Castiel so he was sitting upright, and then he began to thrust his hips upward, milking out his own release. As it were, his cock managed to brush against the older male's prostate, resulting in a sharp cry each time his hips rose off the bed.

"D-Dean," he whimpered, the pleasure becoming so intense it was more of a pain than anything else. He received a grunt in response while he noticed the thrusts became unpredictable. Seconds later, when the angel thought he could take no more, his human gave one final jerk of his hips before shooting his load into Castiel's body. As he slowly dropped from his high, his exhausted lover lifted himself up on trembling legs, only to collapse back onto the man.

"Cas…?" Dean watched in surprise as his friend fell fast asleep there, on his chest.

"You okay, Dean?" The voice brought green eyes away from the bed and towards the dresser of their motel room.

"Yeah," he said, "Didn't know angels slept." Sam finished pulling a pair of pants on, his gaze falling onto their guardian angel. He shrugged, fearing that he knew what was happening. Ever since they had begun to have sex, Castiel had been slowly becoming more and more human. He bled mortal blood now, and had been sleeping the last few times after being spent.

"I'm starved, though." His attention shifted to the bag of burgers that had been forgotten.

"Hey, man. Bring it over here. Those bacon burgers are mine," the older sibling murmured, not wanting to wake the angel. He was sleeping peaceful, the ever-present worry and confusion gone from his face, and his lips parted slightly as his breath continued steadily.

"So, is this gonna be a thing now?" Sam found himself asking while he strolled back over to the bed. He crawled in beside his brother, handing him the first burger. Careful not to drop anything on the sleeping angel, Dean began to inhale the food. The taller man ate more slowly, finding the sight beside him too amusing not to watch.

"I don't know, maybe? You got a little weird back there, but…it was nice." This answered pleased its owner as he finished up the first burger of many.

"You were pretty hot."

"Dude. It's me," he retorted, "Of course I was hot." A smile spread across Sam's lips; he'd walked into that one. He moved to take another bite into his own meal when blue eyes fluttered open.

"Burgers?" he grumbled. The Winchesters looked to each other before Dean grudgingly relinquished one or two to their hungry, Heavenly guardian. But, as he watched Castiel happily ravish the burger, the older human decided it was sort of cute and probably worth the loss.