Fic prompt: Dean finds out about Sam and Gabriel; His reaction?

"Gabriel!"

Dean's eyes opened with a snap. In a flash he'd grabbed the knife from beneath his pillow and jumped out of bed, ready to confront whatever was attacking his brother. It was dark, so he flicked on the lights to see—

"Gabriel, that was amazing."

"Uh, Sammy..." Suddenly registering that the lights were on, Sam looked past Gabriel who was currently sitting on his lap completely naked, and saw Dean staring at them in horror.

"Shit." Gabriel chuckled, and Sam pushed him off and began to get out of bed to go to his brother, before realising that he too wasn't wearing any clothes. Blushing furiously, he snatched a pair of pants off the floor and pulled them on quickly before approaching his brother who appeared to be frozen in shock.

"Dean?" He asked cautiously. When he got no reaction, Sam's apologetic face become worried. Dean was still frozen in horror, not even having blinked since he saw Sam and Gabriel...

Fucking, basically.

Though to be fair, this wasn't the worst scenario that Dean could have seen, Gabriel thought nonchalantly. For example, two days previously when Dean had gone out to buy dinner for him and Sam, Gabriel had turned up at their motel wearing a nothing but a cowboy hat and carrying a bottle of chocolate sauce.

That had been a fun afternoon, Gabriel mused as he watched Sam wave his hand in front of his brother's face. Though that too had been a close call as Dean had arrived back before they'd had a chance to clean up the room. Luckily for Sam, Gabriel tided the room with a click of his fingers and had spirited himself away somewhere else just as Dean had opened the door.

This time it seemed that Dean hadn't been so lucky as to stay oblivious. Perhaps they'd been going at it a bit too loudly in Sam's bed, but to be fair the oldest Winchester had to find out sometime.

"Gabriel, Dean won't move." Sam turned to look at the archangel anxiously. Gabriel shrugged, sucking on a lollipop that had appeared from nowhere.

"I think it suits him better, don't you?" Sam pulled his bitch face, and Gabriel chuckled. "What's wrong with him? Can you fix him?" Gabriel got off the bed, wrapped up in the white bed sheet like a toga, and stood next to Sam.

"Sure I can fix him Sammy; I'm the one who made him like that." Sam gaped at him.

"Why?" Gabriel shrugged again.

"I can read his mind, remember? He realised that he couldn't kill me 'cause I'm an angel, so instead he'd cut off your dick so that we wouldn't be able to sleep together again, which I didn't think you'd appreciate and neither would I, so I froze him for a bit. Your big brother might be dumb, but I gotta hand it to him – he's a quick thinker."

Sam looked rather less put out than before, and smiled at Gabriel.

"Can he still hear me?" Gabriel nodded.

"Good." Taking the knife from Dean's frozen hand, Sam slapped it against his own palm. "Now you listen here, Dean. You better not try and do anything to stop me sleeping - or doing anything else – with Gabriel, you understand? Just because I've got the guts to fuck my angel and you haven't doesn't mean you can interfere." Gabriel guffawed loudly, and at a nod from Sam, snapped his fingers and unfroze Dean.

Upon being unfrozen, Dean's face burnt with embarrassment and humiliation at Sam's last comment, and spoke quickly.

"Fine, you can have your angel, just don't do it when I'm in the same room!" And bolted from the room, leaving a laughing pair of lovers behind him.