If I did own Supernatural, there would probably be a lot more Wincest-y moments. Be glad I don't.
A/N This has been in my head for a bit, and I decided that it deserved sharing. Enjoy!
"What the hell?" Dean cried, leaning back in his chair and crossing his arms. "Why am I bottom?" Sam glanced up sharply from where he sat beside Castiel on the bed watching the Titanic. The angel wanted to know what Balthazar was complaining about, (and also wanted a little break,) and Sam had been all too happy to oblige, being that the Titanic was one of his favourite movies. Throw in some red meat and Dean refusing to watch such a sappy movie and opting for the computer instead, and you had yourself a Winchester bros plus one boys night in.
"Excuse me?" Sam demanded, pausing the movie. Castiel turned to look at the older brother, eyebrow raised.
"What's going on?" he asked, looking between the two.
"Dean, please tell me I misheard you," Sam ground out. Dean stood and went over to his bed, flopping down on it.
"You heard me, Sammy," he said solemnly. "All these damn slash fans keep putting me on the bottom. I mean, I have my top moments, but they're so few and far between..." He scowled. "What about me says 'I'm the bitch'?"
"What's a slash fan?" Castiel asked, still looking confused.
"As in Sam slash Dean. Together," Sam replied, with an earth shattering sense of déjà vu.
"They do know you're brothers? And men?"
"Doesn't seem to matter."
Castiel took a deep breath through his nose. "Though I understand how this might upset the both of you, I've seen gay couples and siblings being mates. Even brothers." The angel shrugged.
"You're there, too," Dean groaned, from where he'd buried his head in his pillow. The angel stared, awestruck.
"Well, ass butt," he murmured, which made Sam chuckle.
"Though it is a good point. Why is Dean bottom so often?" Sam wondered. Dean propped himself up on his elbows.
"I'm the older brother. I should be top."
"I'm taller," Sam pointed out. Dean shook his head, a thoughtful look on his face.
"I'm taller than Castiel. What's he got on me, then?" he asked.
"But I'm older than you!" Dean argued back at his brother.
"Maybe it's because I could actually have sex with, or to be more precise, make you feel like we're having sex without touching you. I don't even have to be in the same room." Castiel looked at the two brothers, who both had traumatized looks on their faces. "What?"
"How do you know? Have you tried?" Sam demanded, looking a little excited. Dean was looking scared.
"Well, no," Castiel replied, to which Sam looked crestfallen. "I do know how, though." Sam perked up.
"Well, let's try it, then!" Sam said happily. Dean looked at him, still a cross between scared and shocked.
"On who?" Castiel wondered.
"On Dean," Sam replied.
"No!" Dean shouted, jumping onto his hands and knees. Sam ignored him. The angel stared at him.
"Come on, Cas," the little brother begged.
"Sam, why?" Dean asked.
"So I have something to use against you," he replied.
"Okay," Cas said, shrugging. He stood and looked down on Dean, who was just getting up, when –
"Oh." Dean collapsed back onto the bed. Sam got up and stood beside Cas.
"Okay, Cas, this isn't – unnnn – funny," the older Winchester tried to say, his voice husky. He moaned loudly, his hands making fists, clutching the bedspread. Cas tilted his head to the side, and Dean jerked violently. "No! Please, Cas, you should – ugh. Mmm, no, that – ha – that shouldn't... it hurts! Ha, ha!" He was panting heavily, his irregular breathing interrupted by loud, pleasured moans. His breathing sped up, and he looked up at his brother and the angel beside him, who both looked on. "Knock it o – oh!" He bucked his hips involuntarily, making noises that Sam didn't even know his brother could make. He cried out loudly when he climaxed, and fell back onto the bed, breathing hard, his eyebrows drawn over his eyes.
If he hadn't been looking away, he would have caught Castiel and Sam both looking down at their pants with mildly confused expressions.
The real reason why Dean was always on the bottom? Sam and Castiel are both perverts.