Castiel was always watching. Just stood there, gazing over them with an air of curiosity and anxiety that made Dean crack worse and worse jokes as he tried to hold up under the unnerving stare. Eventually, Sam knew, Dean would just give in with a curse and a scowl and turn abruptly away, pulling the sheets harshly over his head as he tried to ignore the questioning tilt of Castiel's head.

And it probably shouldn't amuse Sam as much as it did, but there was something about the way the two interacted that had him stifling the grin whenever he took a moment to observe.

It could have been the way Castiel's constant trailing after Dean reminded him of an awed puppy following its master. The slowly blinking eyes and innocently confused expressions on the angel's face whenever Dean tried to joke around with him were a strange kind of adorable, though Sam would avidly deny the thought having ever entered his head. Possibly it was the way Dean flourished under the silent devotion, drinking it in as a replacement for the days when Sam had been Sammy and life was just that little bit simpler.

That thought kind of made Sam a little bit sad though, and he was pretty sure that wasn't the whole truth to it.

After all, Dean looked at Sam with all the love of a brother, fiercely protective and dedicated to protecting him with everything he had, including his life.

But Dean looked at Castiel with simple love, as if that was all that was needed. In the end it wasn't really all that complicated; things had just happened that way, an inevitability to fate that had wound up with everything falling exactly into place just as required. Dean never really had to worry about Castiel, even with his complete inability to understand humans; if Castiel was ever in trouble it wasn't as if he was really made of oh-so-breakable flesh and blood after all. And Castiel didn't really worry about Dean either, always having a quiet certainty that Dean would be there at the end of it all, just as brazen and blunt as ever.

It didn't mean they didn't protect each other. If Sam had a nickel for every time one or the other had casually stepped in to defend the other he'd have been able to buy himself a new laptop by now and give Dean his old one. And by God would he have done that already, instead of finding Busty Asian Beauties shimmering back at him every time he left it with Dean for two minutes. And hadn't that just been the most hilarious thing for Castiel to bring up in the middle of the hunt that time. Dean had almost lost a limb, whirling round so fast he nearly missed the ghost flicker into existence behind him. Sam had been too busy staggering to the nearby couch under deep howls of laughter, but Castiel had been right there, casually banishing her as he raised an eyebrow at the ferocious red shade curling across Dean's cheeks.

Dean had rather blatantly refused to acknowledge any further mention of the subject, turning away and stomping out with an embarrassed scowl to his face as Castiel frowned at Sam, still bellowing with laughter and collapsed across a rickety old sofa that squealed under his weight.

Sam had teased Dean about it for weeks, desperately concealing the smile that threatened whenever he saw the way Dean's eyes nervously shifted to Castiel before he hurriedly changed the subject.

And wasn't that just the most telling factor. It wasn't like Dean was going to change for Castiel, nothing so adolescently romantic as that. But he cared about what Castiel thought of him, cared so much that the idea of Castiel disapproving had him frantically running and hiding before he had to find out.

Sam didn't think he had much to worry about there, if the affectionate curve to Castiel's lips every time Dean scrambled for a new topic was any indication.

The unfortunate ending to the sappy rom-com was that neither one would ever tell the other the truth. Sam could see it already. It wasn't just him either. Gabriel had met his eyes with a wry grin and a quick shake of the head once, a brief interaction that had left Sam blinking bemusedly at the idea that he and the archangel shared a fond exasperation over their respective brothers. But it had confirmed what he already knew.

Dean and Castiel would never shatter the tenuous illusion that separated them, because doing so would break it.

As it was, they were just an angel and a human with a vague fondness for each other. A line was drawn between them, even with how human Castiel was becoming, he hadn't actually fallen for them yet.

Sam had a feeling that the moment they admitted the extent of their feelings to each other, Castiel wouldn't have any choice but to Fall. And Dean, however indignant and self-righteous and demanding as he could be, would never quite ask for that. They all knew that if he asked Castiel would do it, without a moment of consideration. Just utter and complete obedience.

Sometimes Dean would look at Castiel with terror in his eyes, and Sam knew he was acknowledging the amount of power he had over the angel.

Castiel would only look back, a solemn agreement shadowing his features. He knew what would happen too and as much as he might want to be with Dean, he considered himself only useful as he was now. Powerful; a warrior of God. If he Fell he didn't think he would have any further use to the Winchesters, and perhaps that was the thing that darkened his face on the late nights and caused him to drag in a desperate gasp of air before disappearing for a while.

Dean would just let him go, fatigue in every line of his body, before grabbing another can of beer.

Sam didn't quite know what to do on those nights, except hand the TV remote to his brother without the usual scuffle. He would just flash a grin at the grateful expression on Dean's face, then move to go get the sleep he knew Dean would miss that day.

He'd wake up in the morning to the sounds of Dean nagging Castiel about where he'd been all night, and quietly steel himself for the task of watching over them both for another day.

However amusing it got, however hard it was to contain his laughter, he couldn't quite get himself to ignore the desperate longing in every look they shared.

…..

Sorry this is a little less than great… Just a random spur of the moment drabbley… thing… Yushe…