Castiel wasn't nearly as clueless and naive about sex and Dean and Sam seemed to think. It wasn't that he had no idea about these things; quite the opposite in fact. No, the problem was that human sexuality had changed so much since his previous trip to Earth. Not only was there porn - in video and in all manner of kinks - but sex was so much more accessible. Or at least it seemed that way over all. But Cas had been having a hard time finding it.
The last time he had been on earth he had taken a female vessel and things had been so different. So easy. The social cues aimed towards the angel hadn't been subtle and a person's intention was always known. Always clear. Humans, especially men, would come up and whisper in the delicate vessel’s ear about all the things they could do together if only they were alone. And, intrigued, Castiel would fly them to somewhere solitary. Skirts would be hitched or discarded completely and the pleasure was both unexpected and intense.
But in his male vessel it was all too subtle. Women would evade the issue entirely when approaching him and most of the time when they were trying to show interest they were being so subtle that Castiel didn't even know they were flirting. It was confusing. And then there were the men. Most of whom would stare at him and never say anything at all. Cas knew that his vessel was considered attractive, he thought so too; but apparently it just made men uncomfortable and stare at him without approaching. It was frustrating.
But he was not naive. He knew what it meant to want and be lustful. He had just pushed those urges of his vessel down and refused to deal with them while he didn't understand the social cues of the age. (With the exception of course of exploring himself in moments of weakness where he felt too overwhelmed by need.)
He didn't second guess himself as he answered a question about sex. It didn't come to mind that Dean and Sam would find it odd. When the three of them had been sitting in the library looking for a case and Dean had mentioned that someone had died and asked ‘what the hell is -’ as Cas read over his shoulder. It didn't occur to him that he shouldn't explain; That it would seem strange that he knew. So he just smiled slightly to himself and the words tumbled out without a second thought.
“Its a sex act wherein one party, generally the female or receiving party, is bound and suspended. They are then swung to allow for… stronger motion against their partner.”
He looked up from the screen and saw two stricken faces staring at him.
“How do you know that?” Dean finally asked while Sam continued to stare.
“Well… I've taken part in such an act so…”
“Oh god Dean, do you really want to know how ?”
“Jesus, no. Who with?”
The Winchesters questions kept coming and coming and while Cas didn't feel uncomfortable, he wasn't sure that they wouldn't. He cleared his throat awkwardly.
“It was...a long time ago. With a man named Gerald.”
“I'm not gay. I'm not straight. I'm not anything - I have no gender as an angel. But he was straight, I was in a female vessel at the time. As I said it was a long time ago. I'm honestly surprised the name hasn't changed by now…”
“Wait…” It was Sam that was speaking, trying to cover the grin on his face with his hand, “You were receiving when you did this?”
“Yes. I was the one suspended.”
Sam kept smiling, clearly interested in this juicy new piece of gossip; but Dean had gone quiet and was staring overtly. As the information trickled into the hunter’s brain Cas saw a few small changes. His pupils grew slightly larger; he swallowed hard; he brought his knees together. Castiel pretended not to notice, keeping his attention on Sam as he spoke again.
“...how was it?”
Cas became thoughtful; letting his mind wander back through the centuries to dwell on the sensations he had felt in that particular encounter. He smiled. And while he couldn't see his own expression, the faces of his friends seemed surprised by it.
“It was enjoyable. Very enjoyable. And as far as the myriad of encounters I've had go, it was quite intense. It wasn't the most pleasurable experience I've had; but it was far from one of the least.”
The brothers stared. Castiel shrugged. To him it hadn't been a big deal. Just one more human experience to, well, experience. Human experiences were half the point of taking vessels in the first place.
“...myriad of experiences.” Dean swallowed hard again, “how much sex have you had, Cas?”
“In this vessel? Very little. The social conventions around having a male body are...difficult to navigate for me. But when I had a female vessel? A considerable amount. And then if you want to ask about when I have no vessel...well…” Cas furrowed his brow and looked mildly confused “it really depends on whether you consider communion between angels to be sex at all, and which kinds of communion would be regarded as sex...but realistically, outside if this particular vessel; I've had a lot of sex.”
It had been days since the, frankly weird, conversation about Cas’ previous sex life and Dean was struggling to cope.
He had always assumed that Cas just wasn't interested in sex. Or at least that he wasn't interested as an angel. The only encounter Dean knew about Cas having since they'd known each other was while Cas was human. He hadn't seemed at all interested at any other time; but now he was hearing, from Cas directly, that this just wasn't true. That in another vessel he hadn't just had sex once or twice; no, he'd had ‘a considerable amount’ of it. And at least some of it was pretty kinky.
Dean just didn't know how to process the information he'd been given, let alone what to do with it. So when he woke in the middle of the night, tangled in blankets and covered in a sheen of sweat; it took all his will not to take himself in hand and let the dream he was having playback through his mind. It had been as Cas had described the experience of his past; only it wasn't a female body wrapped in ropes and swinging gently from the ceiling when he approached. It had been Cas as he currently was, as Dean knew him, in his male vessel with glowing blue eyes. His eyes had glowed in Dean's subconscious as the angel grew more and more aroused, writhing and straining against the ropes that bound him.
“Fucking hell…” Dean groaned at the memory and buried his face in his pillow. It had been difficult enough to keep his imagination under control when it came to Cas; but after finding out that the reason of his lust wasn't, in fact, asexual - it was becoming impossible to keep himself in line. He was growing curious about all manner of things he would never allow himself to think about before.
Did Cas sigh with content after deep kisses?
What did it sound like when he moaned?
Did he whimper and shudder if he was teased without release?
Did he like it rough?
He must like it rough, Dean figured, if he'd gotten off on being fucked while bound and suspended.
And then Dean's mind was off again and he clung hard to the blankets while trying to calm himself. It wasn't working. The hunter whined helplessly as he tried to ignore the straining organ in his boxers. It was 3 in the morning; he should have been sleeping. He shouldn't have been thinking about his best friend keening against him and begging for more. He'd spent years pushing the feelings down. Pushing down the want and the need. Told himself that Cas wasn't interested, emotionally or physically. Told himself it wasn't fair on the angel, especially since he'd likely hear with his superpowered hearing.
But Castiel was interested in sins of the flesh. At least on some level. And in part of Dean's mind that made it almost okay. His inner voice spoke to him saying that Cas was a creature of sex and baseless urges after all. He probably did the same thing, though probably not about Dean.
And that was the point where it stopped being okay in the hunter’s mind. He couldn't jerk off to the glorious images his brain had conjured up, not when his angel wasn't interested in him at all.
And yet, if Castiel had been interested, there would have been no need for his hand or his imagination at all.
So his brain went back and forth over the ethical dilemma while his body took control by itself. His hand made its way into his boxer shorts and Dean almost moaned from the relief of his own touch. He barely caught the sound, biting his lip hard to prevent its escape. And that was that, it was suddenly too late to stop himself and he let his imagination go to work on filling his mind with Cas’ imaginary moans and pleading.
It didn't take him long to reach his climax; knuckles shoved in his mouth as he bit them hard to hold back his own noises as he spilt, hot and sticky, over his own hand and his shorts.
Calming down took considerably longer and as the sweat on his body cooled the realisation of what he'd just done made its way into his afterglow-addled consciousness. He'd just had a wet dream about his best friend; then jerked off over it. He hadn't just come; he'd come HARD. Harder than during a lot of the sex he'd had.
“Shit,” Dean whispered to the emptiness of his room, “I am so fucked…”