Sherlock began playing his violin with the face he always wore while in his mind palace: focused and concentrated. The notes were solemn, but hopeful.
"Ah, Carry On My Wayward Son. What a classic" Dean said with a smile as he downed his second beer. He looked at Castiel, and they shared a look from across the room.
"What?" Cas asked with a clueless eyebrow.
"May I have this dance?" Dean stretched out his hand.
"Is that what humans do to this song?"
"It's what we do to this song."
Dean and Cas embraced, the latter putting his hand on Dean's shoulders, and Dean took the lead with his hands around his angel's waist. By the second chorus, nothing else existed in the room; not Sherlock, not his violin, and not even Sam, who was passed out on the couch with his head on Watson's lap, who was also passed out. Cas stared at his vessel's feet the whole time; Dean stared straight at his dance partner, with a cornered smile.
Their steps quickened, matching the pace of the song.
Cas couldn't help but smile as he got the hang of being led by Dean. "Surely, Heaven waits for you, Dean, you dance so well."
"Ah-ha, I see what you did there."
"What did I do?"
Dean shook his head with the smile that wouldn't go away. Their movements were gracefully clumsy as they made their way around the space of Sherlock's living room. As the song drew nearer to its ending, Cas lost his balance and began to lean backward. Before Cas had the chance to fall, Dean caught him in his arms and the two landed next to the sleeping pair as Sherlock finished the song with one last stroke, his eyes mesmerized behind closed eyelids.