This is set somewhere in season 8, as you can see.
"So get this:" Sam said as he looked intently at his laptop. Dean rolled his eyes.
"I thought we discussed this. No more cases until we deal with this tablet stuff."
"Dean, that's been tearing you up. I thought a case would let you relax, wind down a bit."
"Yeah, because chasing monsters that can kill us is a great way to take off some stress."
"Look. We have no idea where Kevin is, so we're just going to have to wait. I want to find that kid as much as you, but until then, let's get back to what we used to do."
"Sam is right." The Winchesters nearly jumped out of their seats at the sight of the angel.
"Cas, haven't you heard of knocking?"
"Yes, I have. What's your point?"
"Forget it. What are you doing here anyway?"
"I thought I'd check in on you."
"Where have you been, anyway?"
"I-" A loud clash interrupted them, followed by a woman's voice uttering a string of profanities. The brothers jumped up, instinctively reaching for their guns and slowly walking towards the noise.
"And now we're back in the bunker! What an absolute dick!"
"Who the hell are you?" Sam demanded as he burst through the door.
There were two women in the hallway that turned to face them. The shorter one had light brown hair pulled back into a braid. She wore a dark green flannel over a black t-shirt with worn jeans. The other woman was extremely tall, despite the fact that she wasn't even wearing heels. She was easily the same height as Dean. Her hair was long, and tied back behind a bandana. She, too, was wearing plaid, hers in red. Both women were extremely attractive.
The tall one reached for her knife while the shorter pulled out a gun that looked…exactly like Dean's.
In fact, everything about the two matched. Same green eyes, same pout, same stance as they aimed at each other. And the taller one was a likeness of Sam.
"The question is," The she-Dean said, "what are you two doing in our bunker?" She gestured at Sam with her gun. "And why does he look so much like Sammy?"
"Speak for yourself, you look like Dean!"
"That's because I am Dean." The girl blinked in confusion. "I go by D usually, but-" Castiel suddenly appeared in the room. "Oh, Cas, thank God it's you." She ran up to the confused angel and gave him a quick peck. "Sammy, spray these guys." Sammy nodded and splashed the brothers with holy water.
"Clean." She fished a silver coin from her pocket and pressed it to Sam's and then Dean's arm.
"We're human, see?"
"Okay, that's-" Sammy was interrupted as she and her sister were sprayed in the face as well.
"Can't be too careful," Dean said as he tested the sisters with silver as well. "Happy?"
"Not really. Cas, who are these two?" Cas looked at the sisters for a moment.
"They are you two. Biologically, you are twins. Virtually everything about you are the same, except, well,"
"They have dicks." D finished, still holding the angel's arm.
"To put it one way, yes."
"But where did they come from?" Sam asked.
"They appear to be from an alternate universe, where it seems that everything is the same, but you two are females."
"Sweet. I've always wondered what I'd look like as a chick," Dean said as he checked himself out.
"I can't say I'm impressed," D said, glancing at Dean. "I thought I'd be taller."
"What's that supposed to mean?" D rolled her eyes and walked toward the main room of the bunker. Sam shot a knowing glance at Sammy.
"Great," he said. "Now there's two Deans, and one of them's hot. That'll do wonders for his ego."
"Tell me about it," Sammy sighed.
"Why did she kiss Cas back there?"
"Duh, they're dating. The whole 'gripped you tight and raised you from perdition' line really works wonders. If we're essentially the same, how come your Dean's not with Cas?"
"They're both guys. They like to stare at each other all the time, I guess, but I don't think Dean's ever thought about Cas…that way."
"At any rate, we need to go catch up to our Deans. Lord knows what kind of trouble two Deans can get themselves into."
"So, how did you two even get to this universe anyway?" Dean slouched into his usual chair at the table, ignoring D's pout. It was her chair too, after all.
"You have one guess what slippery little bastard brought us here."
"No idea. Shoot."
"Gabriel," Sammy said as she and her counterpart walked into the room."
"Wait, but he's dead," Sam interjected.
"I guess he's dead here, but we aren't so lucky." Dean snorted. "Anyway, he was missing for a while, and he popped up in the bunker out of the blue, so we chased him, and followed him here."
"So he's in our world now?" D nodded. "Great," Sam groaned. "Like I needed any more of that damn archangel."
"Cas, can't you, I don't know, use your angel powers to find him?"
"He is an archangel, Dean. If he does not want to be found, I'm afraid I cannot find him."
"Awesome," Sammy sighed. "We're on the hunt for an invisible archangel, and trapped in a world where we're guys." She suddenly had an idea. "Say, how well have you been keeping in touch with Charlie?"
"So let me get this straight," Charlie said through the phone. "There are now hot chick versions of you two in this universe, and the lady-Sam is dating the Charlie from their world."
"Yeah," Dean said. "So, if you're not too busy, maybe you could stop by? We need all the help we can get, and I thought you'd be interested in meeting them."
"You persuade me with temptations of women. Very well. I should be able to make it to you guys in about three hours. Sit tight."
"Thank God Charlie's coming." Castiel audibly sucked in a breath at Sammy's expression, but he didn't say anything.
"Yeah, but it's not our Charlie," D commented. "She barely even hunts."
"So Charlie's a hunter in your world?"
"Yeah, ever since the LARPing incident, she had a thing for lil' Sammy here and stuck around. You get sucked into this kind of life, you learn to deal."
Sam thought about that, about all those years ago when he never made it back on Monday. Sometimes he regretted it, to be honest. As much as he loved Dean, this whole mess was something he never wanted to deal with. And now that the trials were screwing with him even more, it was harder to see the bright side.
"Lil' Sammy my ass," she said, standing and towering over her sister below. This broke Sam's train of thought.
"So, why do you wear that bandana?" Dean asked. "Wouldn't it be easier to tie you hair back, like D?" Sammy rolled her eyes.
"Figures you'd think like her. One, keeping a constant supply of hairbands is expensive. Two, this puppy's extremely helpful." D nodded in agreement.
"It's honestly a miracle that she keeps it so clean. That thing has been soaked in blood, monster guts, you name it." Sammy laughed.
"Plus, it keeps this mane in place." She shook out her hair, revealing waist-length waves.
"Your hair is ridiculously impractical," D said. "It's so easy to just yank it if you're a demon or something."
"Yeah, but they haven't. I can tie it up if I need to, I just usually don't." She looked over at Sam's own hair. "We're the same, right. You've been growing that out for what, ten years? Is that all you've got?" Sam ran a hand through his own hair.
"It gets in the way if it's too long," he grumbled. Sammy laughed, flipping the bandana back into place with practiced motions.
"I'd offer you my bandana, but I only have the one, which is surprising, considering how much I use it."
"Okay, can we get back to the matter at hand? I'm regretting even asking about your hair."
"I will go and begin the search. Notify me if you require my assistance." With a flutter of wings, Cas was gone.
"How do you propose we find Gabriel, Mr. Hot Shot?"
"You do realize that whenever you insult me, you're insulting yourself," Dean pointed out. "And I guess we should keep an eye out for any just desserts deaths, you know? His trademark. We haven't seen any of those since he died, so that would be a pretty obvious sign."
"That might take days if he just arrived."
"Well, so far it's our best idea, so we just have to wait it out." D scowled and slid to the floor with her back pressed to the wall. After about a minute of silence, during which Sam and Sammy were perusing the web with his laptop, she stood up.
"I'm going to my room," she announced.
"Hey, wait a sec," Dean said, realizing what that meant. He jumped from his chair and followed her. When he got to his room, she was already sprawled out on their bed. "This is my world, my bed."
"And I'm a guest. Show some respect, Dean." Dean huffed and left. Great. Sam was having some sort of geekfest with his female counterpart, and Dean couldn't even go to his room. He had nothing to do but wait. Where was Cas when you needed him?
He decided to waste his time by making dinner. After all, he could cook pretty well. Let's see, he was making dinner for four, five if he counted Charlie. He didn't doubt that the two girls had appetites to rival his and Sam's, so he grabbed the biggest pot he could find and got to work.
"You're doing that wrong," D remarked from the doorway.
"What would you know? I'm doing this the same way you would."
"Bullshit. I was in a girl's home when I was a kid, and I learned how to cook well. I highly doubt you had that luxury, but I wouldn't be surprised if you did, considering your looks."
"How would it feel to sock myself in the jaw?" Dean threatened.
"Aww, come on. You know you couldn't hurt this face." Dean put on a bitchface and turned back to the stove. D tipped a few shakes of some spice that Dean didn't even know they had.
"What the hell'd you do that for?"
"Taste it," she ordered. He complied. It tasted way better, to be honest, but Dean was stubborn.
"Great, now you've ruined it." D snorted.
"Yeah right. You're just jealous that the girl you stands you up when it comes to, I dunno, everything." Dean made a grab at her, but her size made it easy for her to slip away. "I'm you, remember? All the moves you're making, I'd do the same. You're easy to read, Dean. I'd give up if I were you, oh wait, I am."
"Get out."
"Fine, fine. I'm going to talk to your brother. Maybe he's less dense."
"You just called yourself dense," Dean mumbled, but D was already out of the room. Some girl he turned out to be. All she did was bitch about how he was doing things.
A few minutes later, he heard a surprising sound coming from the library. Was that…piano music? He knew there was a piano in the bunker, but who could possibly be playing? He set the chili to simmer and walked into the main room.
"Lord, I was born a ramblin' man
Tryin' to make a living and doing the best I can
And when it's time for leaving, I hope you'll understand
That I was born a ramblin' man." The sisters were singing while Sam played the piano. Wait-what?
"Sam!" Sam's hands clunked down on the keys, and he looked up sheepishly.
"What?"
"Since when have you played the piano?"
"I never told you because…because you'd make fun of me."
"Tell me Dean," Sammy said. "Do you have half the pipes on you that my sister does?" Dean turned pink.
"I don't sing." Sam grinned.
"The shower says otherwise, Dean."
"Everyone sings in the shower, you know that." Sam struck up a few chords on the piano. Dean sighed and sang begrudgingly. His voice was smooth and low, spilling through the room. The girls nodded approvingly.
"I knew it."
"Of course you did, you're me."
So Sam decided to play some more piano, Dean went back to cooking, Sammy sang, and D helped Dean despite his attempts to shake her from his side. After all, they did have twice the family.
A note about the names:
I know that Dean is named after his grandmother Deana, so the female Dean probably would be called Deana in these circumstances, but I wanted her full name to be Dean because I liked that better. So deal.
Femme Sam's full name is Samantha, and she gets called both 'Sam' and 'Sammy' on a regular basis. Therefore, calling her Sammy to differentiate is not a endearment name like the male Sam, but what she goes as.
Be sure to review! Even if it's just a sentence, it really makes my day and the writing goes 10000x faster.