Written on a prompt from a friend. Enjoy!

If it weren't so funny, Sam would feel sorry for Cas. The blank look, followed by the slight furrow of eyebrows in confusion and obvious frustration at Dean's relentless teasing was almost enough to break Sam's heart. Almost. Yet despite Cas's grumbled annoyances and self conscious almost-blushes Sam couldn't help but stifle a laugh every time. Today was no exception.

It had been a long, exhausting day and no one had complained when Dean suggested relaxing at the local Ma and Pa's diner. Cas was accompanying them at Dean's request; he had popped in to give them an update on the God-hunt, and, as Sam expected, because he simply had nothing (or no one) better to do. Dean had been insisting more and more that Cas come along with them, and Cas had seemed more than happy to do so. At first Sam hadn't really given it much thought; besides Cas's whole mighty-smitey attitude that he sometimes had he liked the angel and enjoyed his awkward but amusing company. It didn't take him very long after Cas started 'hanging out' to notice the lingering glances between the two, the way Dean's hand would lightly brush Cas's, or how Dean would contemplatively lick his lips every time the angel spoke. There was something going on here. Sam was pretty sure of it. The fact that Dean kept glancing in the rearview mirror every ten seconds to make eye contact with their backseat angel didn't have anything to do with those assumptions. Definitely not.

"Try Pa's seasoned sausage," Cas read as they entered the restaurant. Dean muttered something Sam couldn't hear, and he watched the familiar confused expression settle on Cas's face - "Who?" Dean just smiled mischievously and followed the waitress to their booth. They assumed their regular arrangement when Cas was with them – Dean and Sam on one side, Cas on the other. They sat silently for a few moments, until Sam felt some strange movements under the table, and something bumped into his foot, and oh my god were they playing footsie? A not very well concealed smile flitted across Cas's lips and Sam thought he was going to hurl. It was weird enough that his brother had a thing with a dude, who was also an angel, but now he was doing cutsie chick things? This was going too far Sam decided and inhaled to make a comment, but was cut off by the waitress.

"What can I get you guys?" the barely legal, tight shirt, big breasted girl with flowing brown hair asked.

"I'll have the double bacon cheeseburger with fries and a coke," Dean ordered without even glancing at the girl, who was subtly arching her back and pulling at her shirt, stepping even closer Dean, but to no avail. The elder Winchester's eyes were not wavering from his…er…the angel. Sam just shook his head and ordered his chef salad, dressing on the side. The waitress left, looking thoroughly disappointed.

Sam glanced down at his watch. They had been waiting for five minutes and thirty seven seconds. It was about time…five…four…three…two…

"So Sam," Dean broke the silence right on cue, looking at his brother with far too innocent eyes that didn't fool Sam in the least. "Didn't you say something about doing some research in the library tonight?"

"Um…yeah I did." He hadn't. "I have a lead on the murders in Michigan I want to check out." He didn't. "You can come if you want." He won't.

"Nah," Dean responded, as expected. "I wouldn't want to cramp your style." Sam gave a humorless laugh and shot a glare in Dean's direction. It looked like he would be spending another night at the library (note: bar) while his brother caught up on sleep (note: had gay sex with an angel). Or at least that's what Sam assumed they were up too, as he highly doubted they were having deep, philosophical conversations pretty much every night for the past three weeks.

Finally their food came, Dean's enormously huge cheeseburger slammed in front of him by their disgruntled waitress. Cas's eyes widened in shock at Dean's choice of meal, and Dean scooted it towards him.

"Want some?" Dean offered. Cas's brow furrowed slightly.

"I don't think yours would fit in my mouth," he said seriously.

Silence. "That's what she said," Dean said.

Cas looked thoroughly confused. "Who is she?" Sam choked on the water he was just about to swallow. Dean snorted and shoved his face with hamburger.

"I don't understand what is so funny," Cas stated with the usual frustrated voice he assumed when the joke was on him, looking pointedly at Sam who had started to cough to hide his laugh.

"Don't worry about it," Dean mumbled through his mouthful of food. Cas looked unsatisfied but didn't say anything further.

After dinner they checked into a nearby motel. Dean tossed Cas the keys so he could unlock the door while they unloaded their stuff. When they approached the room, Cas was still fumbling with the keys.

"None of them fit in the hole," he said pointedly. Sam snorted with laughter, earning him a confused glare from Cas.

"That's what she said," Dean muttered, fingers grazing Cas's hand (unnecessarily Sam noted) as he grabbed the keys. Cas hadn't lied, the keys did not fit in the hole, and Dean went to get them exchanged from the front desk. As soon as he was gone, Cas turned to Sam looking perplexed.

"Sam," he said and paused.

"What's up?"

Cas looked into Sam's eyes earnestly. "Why does Dean always demean what I say? I don't understand his humor."

"He's just teasing you," Sam reassured. "It probably just means he likes you." It was almost sickeningly adorable the way Cas's eyes lit up at that. Sam needed to talk to Dean about this. Tonight. Or maybe not…the car keys chucked at his head made it pretty obvious Sam was not wanted around for awhile. Next time, Sam thought as he gathered his stuff for his 'research', they were getting two rooms.

Castiel was confused. Which was generally how he felt around the Winchester's, for many reasons, but this was different. It seemed that everything he said had been said by some other woman that Dean obviously harbored some feelings for, if the smile that played on his lips every time he mentioned her was anything to go by. And yet, when he had inquired to Dean who this other person was that he had feelings for, Dean had brushed it off, assuring Cas that there was no one else he would rather be with (and then proceeded to take of his clothes with his teeth). He had been reassured for awhile, but Dean didn't stop referencing this woman, and a strange twinge began to grow in Cas's belly. He couldn't understand what such simple phrases had to do with this mysterious woman, but Dean was relentless.

Driving. "This is slow and confining." "That's what she said."

Eating. "It's too hard to bite." "That's what she said."

Shouting. "Dean! I don't know where you're coming from." "That's what she said."

Cleaning guns. "I don't know where this goes in." "That's what she said."

Raining. "I'm getting wet." "That's what she said."

Escaping. "I couldn't see it coming." "That's what she said."

Smiting. "Nothing could survive my touch before I lost it." "That's what she said."

Interneting. "It's stuck this way." "That's what she said."

Hunting. "It sprayed me in the face." "That's what she said."

Drinking. "It feels warm going down." "That's what she said."

…You get the idea. It was starting to annoy Castiel, and that feeling in his gut twinged stronger every time Dean brought her up. Despite their nightly romps in the motel rooms, Castiel was beginning to doubt that Dean was completely over this woman. Why else would everything Cas said remind Dean of someone else? Was he just substituting Cas for someone else? These feelings were beginning to wear on Castiel, and what with the world ending and all, there hadn't been many opportunities to talk to Dean about it. Especially since every moment they had to themselves, Dean would just rip off his clothes and Cas would forget his questions for awhile.

The only comforting thing was that Cas wasn't the only one subjected to Dean's torture. Sam also said things this promiscuous woman had said, but he took it far more lightly than Cas did, but that could be because Sam wasn't boning Dean every night.

At any rate, Castiel was tired of it. And his search for God had been increasingly stagnant, which did nothing to help his frustration. So at the bar when Sam, who had a little more to drink than he should have, and wondered aloud about his bottle, "if I squeeze while I blow, will it change pitch?" and Dean responded with a snort "that's what she said" Cas decided it was enough.

"I'm done," he said and zapped back to their hotel, mostly because he had nowhere else to go. He paced around for awhile, trying to ignore the twisting feeling in his gut that arose every time he thought of Dean with another person. It wasn't fair for Dean to be so callous about discussing his past relationships. It made Cas, who had never…been…with anyone before, feel left out and childish, which was ridiculous considering he was millennia older than Dean.

The door opened abruptly, causing Cas to jump, and Sam entered alone.

"Where's Dean?" Cas asked sharply. Sam shrugged.

"He stayed back at the bar for a few drinks."

"Hmph. Probably to meet up with his woman," Cas muttered, really wishing he had some vodka. Sam blinked in surprise.

"Are you…jealous?"

Cas crossed his arms and looked offended. "No!" Sam raised an eyebrow. "Well…maybe."

Sam pulled out a chair to sit in, and Cas plopped on the bed. "What's up Cas?"

Cas was silent for a few moments. "I have been feeling conflicted." Sam stayed quiet, encouraging the angel to continue. "I do not understand why Dean keeps talking about this woman. He won't tell me who she is, even though everything I say is apparently something she's already said."

To Cas's dismay, Sam laughed. Cas glared. "This isn't funny." Sam just shook his head, smile plastered to his face. He couldn't believe he had to explain this to an angel. An angel who was in love with his brother, no less.

"You don't have to worry Cas, there's nothing going on with Dean," Sam reassured. "He's just making a joke."

"I don't understand," Cas sighed, starting to really hate humanity's sense of humor.

"Well," Sam paused, trying to decide how best to explain this. "When someone says something dirty, you say 'that's what she said' after, just to be funny."

"Dirty?" Cas asked, trying to process this information.

"Dean, with his seriously digressed sense of humor, thinks it's funny to turn everything you say into a sexual joke, because, you know, you don't get it."

Cas blinked. "So there is no woman?"

"No Cas, there's no woman," Sam smiled, feeling genuinely sorry for the angel's lack of social knowledge.

"And he's just turning everything I say…sexual?" Sam nodded and tried not to notice how Cas's eyes brightened at that.

"Well, this is welcome knowledge," Cas stated, his voice a mixture of embarrassment and excitement. "Do you think Dean thinks I'm…sexy?"

At that moment, Sam would have paid a million dollars not to be there. The obliviousness to what Sam had really explained, and hesitant hope on Cas's face was like that of a teenager's first experience with love (or lust). Which Sam supposed was pretty accurate, considering Cas was – or had been before he met Dean – a virgin to busy following Heaven's orders to know anything of love. It was cute almost. In a sickening way.

"Um…" Sam rubbed his neck and gave a short laugh, really wishing he didn't have to answer this. "Yeah Cas, I think he does. And I think he's pretty lucky to have you around."

Cas smiled. "You're good Sam. No matter what anyone tells you. I think that we should be friends." He looked hesitant, as if not sure how Sam would feel about this.

"Thanks Cas. I would love to be your friend." Sam had to resist the urge to pat Cas on the head like a proud puppy, which he wasn't sure would be a good start to their new found friendship. Instead Sam turned on the TV and they watched Dr. Sexy M.D. until the rumble of the Impala cued Dean's entrance.

"How goes the sleepover?"

"We weren't sleeping," Cas responded. Sam stood up, and grabbed the keys from Dean.

"I have some research to do tonight. I won't be back for awhile, so don't wait up."

"Don't work too hard at it," Cas said as Sam was walking out the door.

"That's what she said," Dean deadpanned. Sam looked back to see Cas smile, and sent him an encouraging wink before pointedly slamming the door shut.

Five hours should have been enough. Sam had waited until the bars closed, giving them optimal time to 'work things out.' He didn't know if it was the angel mojo, or what, but they shouldn't have been able to go at it for five hours straight. Apparently, Sam was wrong. And his mistake would be seared in his mind forever. The image of his brother and Cas, in a position he wasn't sure was even possible, was something that would haunt him at night for a long, long while. Dean was moaning something that Sam couldn't really hear, but he thought the caught the words feathers, tongue, and something he would give up his first born child not to have heard. This was proceeded by Cas giggling, another noise he never though he would hear, and a breathy "that's what she said."

It was then that Sam realized. "Come on guys. That's my bed."