A/N: While this story and it's endgame is Destiel, I feel I need to point out that there will be some Sastiel, too (in case anyone missed it in the summary). M rating is for adult content, m/m. There will be angst, hurt, lies and misunderstandings, but it will have a happy ending. This story is complete, there are 7 chapters in total, and I will aim to update once to twice a week.

Best Laid Plans

Sam had only wanted to help. Honestly, that was all there had been too it. No ulterior motive, no personal gain. Just trying to give two people he deeply cared about a push in the right direction because they couldn't. How was it he ended up here? All of them sitting at the table, staring daggers at each other, or more precisely at the wall, and the atmosphere charged like the smallest spark would end up causing a supernova? Which most likely was what would be about to happen any second now. If only he hadn't opened that fucking door that Friday three weeks ago. If only Cas had locked it … If only Dean hadn't been a secretive moron … if only… None of this would have happened…

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3 weeks ago:

"Oh my god," Cas groaned and threw his head back. The feeling of intense pleasure was building up fast with each stroke of his hand around his cock. He was sprawled back leisurely on his bed in the room that he was allowed to call his now. He had disposed of all his clothes as he wanted to do this properly and take his time. See if this whole sex thing really was as big of a deal as most humans seem to make of it.

These primeval urges had become more prominent for a while now, definitely since he had fallen, and they had become harder to ignore despite him having spent a good few weeks feeling lost and refusing to accept that being human was his lot now. But in the end he had faced the facts and started to adjust and, like so many other things he had to get accustomed to, Castiel had decided that it would be best to give into this part of him. And he had preferred to do so under controlled circumstances, not when the impulses were threatening to overwhelm him.

The initial weirdness of touching himself had only lasted moments, quickly replaced by the actual gratification of stimulation. Of course he had experienced his body being aroused before, back when he still had his grace, but then it had been a plain physical reaction, detached from his angelic self and easy to compartmentalise. Also he had never really felt such need to act on it. But since his fall it had become like an overwhelming sensation at times. A deep pulsing and longing and tingling of his whole body, making his stomach churn in a near painful way. What's more, it had the bad habit of repeatedly occurring at the most inconvenient of times, especially around Dean, which definitely was one of the few things Cas was not prepared to share with the man. He would not want to burden his friend with the more than friendship like feelings he was harbouring for him. He went through great length to hide how he felt from Dean and at times it seemed like this had become his prime past time. Just one of those facts in life Cas would have to get used to living with, just like having lost his grace, as clearly Dean's sexual attraction lied with the female part of the human population. If there was anything that Cas had learned about humanity so far, it was that they put a great emphasis on their sexuality and everything that came along with it.

But in the end all that pent up sexual frustration had to go somewhere, and Cas had made up his mind to take a leaf out of Dean's book, and decided to 'clean out the pipes'. Dean had over the years alluded plenty of times to ways of getting the 'job' done and pleasuring yourself. The last time had been but a few weeks ago, when Cas had quickly excused himself, as he did not need to have that conversation again, let alone would have been able to sufficiently hide his embarrassment. But awkwardness aside, the advice had seemed valid. He had been given this whole endeavour some serious thought over the last few days, and decided that his bedroom had seemed the best and most private place to explore his body and what made it tick.

Cas kept moving his hand up and down his shaft, swiping the thumb over his head, learning all those spots that made his cock jump and twitch and shoot an extra jolt of heat and pleasure through him. He watched the screen mesmerised, trying to incorporate some of the things he saw into increasing his own pleasure. He teased and slightly twisted his nipples, just like the guy had done a minute ago, while pumping and thrusting into his closed fist, marvelling at the feeling of his increased heart rate and respiration. He loved the way his whole body was reacting to something as simple as stroking. The ex-angel let out another low groan and gripped himself a bit harder. This had been long overdue and now, as he was doing this, Cas had no idea why he hadn't experimented with this earlier.

The dull moans and dirty talk echoing through the room from the movie he had put on to get him into the mood was doing its part to bringing him closer to the peak. Seeing sweat slick body sliding up against sweat slick body had his mind enthralled and his pulse quicken even more. Still watching the action, Cas imagined that it was not his hand but someone else's that touched him there, and images of green eyes were flashing before his suddenly closed eyes and he bucked up harder into his hand, lifting his hips off the mattress. His toes started to curl and he could feel his balls drawing up tight. He let out a long low whine and a slightly blasphemous (not that he cared at that moment) "oh my God", as he could feel every muscle pull tight and instinctively, he gripped his erection even harder and started to stroke faster, needing that extra friction so badly.

"Hey Cas, have you seen … OH FUCK! I'm … sorry dude!"

Cas' eyes flew open in a panic, just in time to see the bobbing strands of Sam's hair disappear behind the door again before it was firmly shut close in a loud bang.

"Sam? Oh crap!" Cas shouted while frantically scrambling for any piece of clothing he could use to hide his nakedness with. Feeling his already flushed cheeks heat up even more and his stomach turning like he was going to be sick, which actually seemed like a real possibility for a moment.

"No dude… oh my god… I'm sorry… I should have knocked!" Sam yelled through the door, sounding at least as embarrassed as Cas felt. "It's like 3 in the afternoon CAS!", Sam added not very helpful, but as though that would excuse his bursting into Cas' room unannounced.

"Shit! Just… erm… carry on I guess…?" Sam added after a moment before he scurried away and down the corridor into the kitchen. Still being ill from the trials or not, he had never needed a drink so badly in his life and he was going to have it right the fuck now.

He grabbed a glass off the shelf and took the bottle of whiskey out of the cabinet before heading to the table. He slumped down on a chair and poured himself a double; hell a triple would probably be better.

"Fuck, fuck, fuck," he was mumbling repeatedly under his breath as he took a big gulp, not particularly enjoying the sharp burn it left in his throat, and carded his other hand through his long hair. It was not every day that you walked in on your friend stark naked and about to shoot his load. But embarrassing as that was that was not even it. It was the glimpse of what it was that Cas was watching on his laptop that had Sam all tangled up inside. And he couldn't even say that on some level he hadn't had his suspicions, even though if asked he wouldn't be able to say why. But, honestly, he had never given it too much thought; he generally had other things to keep his mind occupied, like staying and keeping other people alive, not speculating about their sexuality. But now he couldn't help himself because, clear as day, Cas had been getting off to two dudes fucking each other's brains out, and well, he chuckled manically as he took another sip of the amber liquid, it seemed like Cas for all his talk and incomprehension of human sexuality had found his preferences.

And of course Sam's mind wandered to what that meant for Cas' relationship with Dean. These two were inexplicably tangled together in his brain, and while he had chosen in the past not to dwell on it he was not stupid. He had noticed the looks Cas chanced at Dean and vice versa. Hell, he had years of that to the point of it making him feel uncomfortable at times. But he had always managed to convince himself to put it down to their "special bond" or whatever if was they were sharing.

Another reason for Sam not having questioned things more was the fact that clearly, Dean didn't swing that way. Sam was pretty sure of that, despite his teasing over the years to the contrary. But now that Cas … and… oh … was that why Dean had started acting strange lately? Gone all creepy and secretive around them? But thinking about it, it was mostly around Cas. Did he know or did he somehow find out about Cas? Shit, if so, Dean needed to grow the fuck up. So what, Cas liked dudes and maybe Dean in particular (Sam had his suspicions about that one too). Dean had faced worse and Cas was still first and foremost their friend.

Cas scrambled around, picking and putting up his clothes as fast as humanly possible (and huffed out a bitter laugh at that idiom). His mood had gone from ecstatic to feeling like he wanted to die within a heartbeat. His arousal had all but disappeared, being replaced by something he thought might be shame. He would never understand how humans could stand getting tossed around by their emotions like that; all he felt was being out of control and weak, and he loathed himself for it. But mostly, he felt the need to go after Sam and explain. He had no idea what had just happened and why it had left him so flushed and mortified. It was a totally normal thing to take care of. Well, if Dean and Sam's own advice was to be believed. But somehow having Sam see him exposed and vulnerable like that, plus the idea of Dean finding out about this, had him spiral into a panic.

Not bothering with socks or shoes, he quickly opened his door and went to look for Sam. Instinct told him that he would be in or somewhere near the vicinity of the kitchen, which was exactly where he found him, clutching a glass like his life depended on it. Cas didn't feel comfortable going all the way into the room so he hovered around the entrance and cleared his throat.

"Sam?"

"Huh?" Sam spun his head around to see a very bedraggled but thank goodness fully clothed Cas stand in the doorway to the kitchen, shifting nervously on his feet, not meeting his gaze.

"I'm sorry about …"

"No. Don't apologise. I was out of line not to knock." Sam replied still sounding uncomfortable but looking at Cas and waiting for him to meet his gaze. "Although just for future reference, it's generally a good idea to lock the door when you … you know … indulge yourself." Sam needed another gulp of his drink.

Cas nodded his head in silent agreement. Yes, he had probably been stupid in assuming that a closed door alone meant you wanted not to be disturbed. Well another thing to add to his long list of 'do's' and 'don't' of humanity. He finally felt brave enough to look up and meet Sam's eyes and his mouth was turned up at the ends giving him a small smile, like he understood that this was all new to Cas. But Cas still shifted, ill at ease. His mind dominated by the thought of Dean and how he did not want him to find out, what he wasn't even quite sure anymore, just all of this.

"Please don't tell Dean…" Cas implored, still not daring to step further into the room.

"Don't tell me what?" Dean's voice drifted towards them from somewhere behind Cas and sounding more than just a little curious. Speak of the devil. Cas tensed and his eyes looked at Sam wide and panicked and he went pale like he was about to faint.

"I thought we were past the keeping secrets from each other stage in our relationship," he said while pushing past Cas and into the kitchen, heading straight for the fridge and grabbing a beer. His voice sounded light and teasing but the slight waver was easy to pick up for anyone who knew him.

Dean emerged again, leaning casually against the wall. His eyes were flickering between Cas and Sam, who both looked like they had been caught with their hand in the cookie jar.

"'S nothing." Sam was the first one to find his voice. "Just Cas … asked me some advice on some personal stuff and…"

"Yes, nothing of import." Cas added all too quickly for Dean's liking. Confirmed by the way his friend was holding himself and shifting like he had something to hide.

"Yeah, whatever." Dean huffed and rolled his eyes. Were they really trying to feed him this bullshit and expecting him to believe it? He didn't need reminding that he had been stupid enough in the past to fall for cheap excuses and half truths, because he had wanted to believe, but he had learned his lesson since then. He eyed Cas warily and couldn't help his stomach plummeting at the idea that Cas yet again might keep something from him. Even worse, chose his brother to confide in instead of him. "Not that it's any of my business, right Cas?" he added before he walked straight back out and into his room. 'Personal my ass'. Once, Dean had been the one Cas would have turned to with anything personal. Personal, what did that even mean? Dean slammed his door with more force than strictly necessary and flung himself on the bed.

God knew Dean had been patient with Cas. He could never imagine what Cas must have felt and gone through when he had his grace ripped out of him against his will. And he still remembered the weight that had lifted off his shoulders when he first had set eyes on Cas again, after almost a week of believing him dead. But all too soon that feeling had been replaced with dread and apprehension. Dean had tried to ignore the way he had been deeply hurt by everything Cas had done and how he had felt betrayed by him. But eventually these feelings had caught up with him and the anger at Cas, and the relief and happiness at seeing him alive and in one piece, had started a war inside Dean's head that tore him apart bit by bit from the inside.

The situation hadn't been made any easier by the way Cas had seemingly been walking on egg shells around him those first few weeks, and every time he had tried to apologise, Dean had brushed it off until he eventually just accepted the apology because he couldn't bear to see Cas' broken and defeated face any longer. And for a short while they both could have fooled themselves into thinking things could go back to the way they had been, well, safe for the fact that Cas was now human and for the first time needed their actual help. And despite everything, Dean had tried to give it to him. But the inevitable physical closeness and time spent together had sent him into a new spiral of fear, not ready to face some of the deeper issues of his and Cas' relationship.

Throw his worry about Sam and whether he would ever fully recover from the aborted trials in this mix of his mostly unnameable emotions towards Cas, and Dean should not really be surprised at the way he was feeling off kilter. If he would allow himself to dwell on it, he would probably say he was like a bow so tightly pulled back that it could snap at any second. He knew himself well enough to admit that all it would need was one wrong word, one wrong action for him to snap. And just now in the kitchen it had gotten awfully close. Too close. And he would not allow himself to go there. He didn't purposefully want to hurt his friend or his brother.

But even hiding in the sanctuary of his own room did nothing to help him calm down. This bunker, which was supposed to be their home, now had become like a prison at times and right now Dean had one of those moments where he couldn't breathe. He had experienced these almost panic attacks more and more lately and knew he just needed to leave, go somewhere where he could forget just for a little while.

With one long swig he emptied the last of his beer and grabbed his car keys that he had unceremoniously thrown on his bed next to him. He headed down the corridor, stalking past the kitchen with an "I'm heading out, don't wait up for me". He didn't' like the way Cas had moved into the kitchen, and he and Sam had looked like they were whispering to one another, looking too intimately for his liking, but he decided not to give this any thought.

"Hey… where you're going? You just got in!" Sam yelled from where he was still sat at the table.

"Just getting some air!" Dean shouted back and with that he banged the front door shut.

Cas and Sam looked at each other, startled and shaking their head in silent understanding and worry about Dean.

Cas was just about to open his mouth when Sam cut him off.

"I don't know…" he stated anticipating Cas' question.

It took Cas one look at Sam's face to realise that he was telling the truth and he nodded his head, letting his eyes fall back to the floor. Their whispered conversation about Cas and how Sam didn't have an issue with him liking guys and how, of course, he wouldn't tell Dean as there was nothing to tell, all but dead.

Cas hovered for a moment until he realised their talk was truly over. "Thank you Sam, you are a good friend," he stated before going back to his room.

Sam sighed and his head was hurting from the alcohol. He needed a moment to process. After a short time of doing just that, the kind of surrealism of what had happened earlier hit him. Sexuality aside, to have someone walk in on you while jerking off is just plain cringe-worthy, and now he felt sorry for Cas. Sam chuckled as he remembered the one and only time Dean had walked in on him getting off and of how he had wanted to die and had not been able to look at Dean for like two weeks. Poor soul. Sam shook his head in amusement as he thought of Cas and finished the last of his whiskey.

But Dean, Dean apparently didn't know about Cas. So why was he acting the way he did? Dean had been off lately, and not just his normal kind of off. Like acting really weird kind of off. If it wasn't because of Cas, then what on earth was going on with him and inside that head of his? All this secrecy could not mean anything good if their past track record was anything to go by. And frankly Sam was tired of yet again being left out of Dean's life. He really had thought they both had turned a corner and had left that kind of behaviour behind for good. That they could trust each other with anything, but he couldn't shift the feeling that he might be wrong about this yet again.