AN: A little funny, a little romantic, a little porny, hopefully not too cheesy. Title from Jack's Mannequin song "Swim". Feedback always appreciated!

"Dean, I do not understand the point of this."

Dean sighed turning away from moonlit pond. "The point Cas, is that it is way too hot to sleep in Bobby's un-air conditioned house. When Sam and I were kids we used to come out here and cool off."

"In the water."

"Yes, in the water" Dean said rolling his eyes.

He'd been relieved when Cas decided to become human and stay after Lucifer had been sent back to the slammer. After two years, a dozen beers, and, oh yeah, an apocalypse, he'd gotten used to having the guy around. He steadfastly refused to consider this any more closely and had been ignoring Sam's increasingly pointed comments on the subject.

"And Bobby's shower could not accomplish this?" Cas said eyeing the inky water suspiciously.

Dean started toeing out of his shoes, "Dude, you decided you wanted to try being a human remember? Well, consider this lesson… thirty-seven? Thirty-eight"

"I believe thirty-seven was 'never let Sam eat Mexican food before a long car ride' and thirty-eight was 'Bill Murray is next to godliness'," he recited drolly. "This would actually be lesson forty-two."

Dean paused, his hands on the hem of his shirt, "Hmm, forty-two is actually the ultimate answer to life, the universe, and everything."

Cas gave Dean one of his maddening head tilts, "It… What?"

Dean waved his hand, "Never mind, we'll come back to that one. Forty-three is 'always go skinny dipping on hot night.'"

He pulled his tee off, "Unless of course you're a hot coed and there is a deranged serial killer on the loose."

Cas' wide eyes were taking in Dean's chest and he felt himself flush. He cleared his throat and turned away to unbutton his jeans. "So, make with the, er, stripping."

Dean quickly dropped his jeans, leaving boxers on, and waded out into the water. The pond was small and shallow so it felt a tepid bath. Not refreshingly cold, but comfortable, soothing.

Once the water was chest high he lowered himself until he was completely submerged. He turned under the water and started swimming back toward the shore. When he ran out of breath he surfaced.

Cas, wearing only a pair of black boxer briefs was standing ankle deep, his pale skin shimmering in the moonlight. Dean's eyes traveled up, taking in Cas' well formed body, and his cock gave an interested jerk.

Well, fuck. Why had he thought this would be a good idea?

"Um," he croaked, "you should come in. The water's nice." He started gently paddling deeper on his back, never breaking away from Cas' gaze. Cas just nodded and started wading toward Dean. When they both stopped moving they were about a foot apart with the water shoulder deep, still staring at each other.

Fuck. Fuck. Fuck. That word repeated in Dean's head to the rhythm of his pounding heart.

If Cas was a chick, he knew exactly what he'd do now. But Cas was dude and he'd technically only been one for, like, less than a month. And, most importantly, he was Dean's best friend and Dean did not want to fuck that up. So, he did the only logical think he could think of.

He splashed water in his face.

Nobody ever accused Dean Winchester of being mature.

Cas was stunned for a moment but then his lips started to curl up, "I take it this is a traditional custom?"

Dean breathed a sigh of relief and gave Cas his biggest shit-eating grin, "Yep."

"Well, in that case…" Cas splashed him right back.

For the next few minutes they chased each other around splashing, though Dean had the advantage of being able to duck underwater and swim. Cas had good reflexes though, so at one point when Dean surfaced just behind him Cas spun around caught his arms, "Gotcha!"

Laughing, Dean tugged his arms toward his chest but Cas didn't let go so his face ended up only inches away from Dean's. The laughter drifted off and neither man made to move away. Cas licked his lips nervously and leaned in slowly. Dean, for his part, was completely paralyzed as Cas pressed a gentle kiss to his lips.

Cas pulled back and dropped Dean's arms. Seeing the shocked look on Dean's face he started panicking, "Sorry, I should not have—"

Dean cut him off when he gripped his face crashed their lips together. He swept his tongue along Cas' lips and the other man opened for him. They explored each other's mouths until they ran out of air.

When they finally broke apart, Dean pressed his forehead to Cas' groaned, "You have no idea how long I've been wanting to do that."

Cas just offered one of his minutely pleased expressions and he leaned in to kiss Dean again. It was slow and tentative at first, one hand curling around the back of Dean's head to tangle in his hair, the other, sliding gently up Dean's left arm to fit over the handprint scar.

Maybe it was all in Dean's head. He'd touched that scar a million times and it wasn't particularly sensitive anymore, but there was something incredibly sensual and erotic about Cas' hand on that spot. Like he was reclaiming that which was rightful his.

He moaned into Cas' mouth and reached out to pull the other man's body flush against his. Cas gasped and Dean could feel his skin prickling under his palms. He paused a moment, leaning back and searching Cas' face for a sign that this was ok, that he wasn't moving too fast.

Cas, for his part, followed after Dean without hesitation. His eyes set with the same forceful determination Dean had seen that fateful day they battled Lucifer and the lords of Hell.

Now it was Dean's turn to shiver.

Their lips met and Dean dragged his hands slowly down the other man's back, coming to rest on his waist. He jerked Cas forward, slamming their hips together, reveling in the feeling of Cas' dick hard against his own.

He dreamt about this he now realized. About the gentle firmness of his touch and the scrape of his stubble. The way he tasted sweet and he powerful heat of his body pressed close. Those mornings he woke hard and ached with a longing he didn't yet understand. It was Cas. It was always Cas.

And that's how he ended up here, grinding their bodies together on the verge of coming in his shorts like a teenager. Cas writhed against him soft moans and gasps punctuating his thrusts, hands roaming searching for purchase. Dean kissed his way along Cas' jaw, sweeping down to suck gently on his pulse point, all the while rocking against him.

Dean mouthed his way up Cas' neck until he bit gently on his earlobe and whispered, "come for me Cas." Cas whimpered and his hips stuttered. He was so close.

"That's it Cas, let go," he breathed and Cas came with a strangled sob. The sound of the former angel coming undone was too much, Dean came hard, vision whiting out like those moments when he'd seen the edges of Cas' true essence before he'd have to shield his eyes from the blinding brightness of it.

When he finally came back to himself he found himself clinging to Cas, breathless, his legs feeling like jelly. He thinks it's a miracle they didn't sink below the water, drowning into oblivion. Dean loosened his hold, pulled back, and shuddered at the loss of heat.

Cas was… breathtaking, is the only word Dean's mind conjure even though it's ridiculously girly. But the way his hair was mussed, jutting out at odd angles, his lips flushed and swollen, eyes wide and awestruck, staring at Dean like he's a fucking… god or something. And there's the part of Dean that wants to crack a joke about how he's a sex god or a love guru or some shit but he can't. Because for the first time in his miserable existence the sex wasn't about sex, it was about something else.

He remembers this movie Sam was watching one night years ago, not that long after they'd left Stanford. There was this song, something about finding your other half, trying to sew your selves back together. He remembers Sam telling him it was based on Greek philosophy or something and he'd had some hilarious joke in his head about that. But Sam had looked so wrecked he couldn't say anything. He watched the rest of the weird ass musical with him in silence.

He thinks he gets that now, what the song was about. It's beautiful and it's terrifying and Dean can't breathe. He's drowning and he's afraid of dragging Cas under with him.

The enormity of the situation hit him for the first time. Cas gave up Heaven for him, surrendered eternal peace to wallow in muck with a mud monkey.

Nobody ever accused Dean Winchester of being the sharpest tool in the shed.

Cas must have seen all of these emotions float across his face. "Dean," he said firmly, one hand gripping his mark, the other wrapped tightly around the back of Dean's neck, eyes boring all the way into Dean's soul.

Despite this intensity, Dean felt calmer. He gave Cas a thin smile. "I don't… Cas… I don't know how to do this."

"Do what?" Cas asked his thumb tracing gentle circles along Dean's throat.

"This, a, a relationship, or whatever this is…" Dean trailed off worrying his lip between his teeth.

Cas shrugged, "Neither do I. We're making it up as we go."

And Dean had to smile at that, "Well… ok then." He leaned down and gave Cas a quick peck on the lips. "C'mon, let's go back."

The waded back to the shore; slipped on their shoes and gathered their belongings. Dean was still a little freaked out about everything but he wasn't panicking, didn't feel as though a riptide was ebbing, waiting to knock his legs out from under him.

"So," Dean asked between long lazy kisses, "number 43's good right?"

"Yes," Cas smiled indulgently, "43 is definitely good."