Dean and Sam introducing Cas to all the classic movies one evening - Star Wars, Star Trek, Indiana Jones. They stay up all night watching movies and stuffing themselves with beer and popcorn until Sam and Cas - the weaklings - pass out around five in the morning half-way through the first Indiana Jones movie.
Cas’s head is resting on Dean’s shoulder, one arm around Dean’s waist. Sam’s head is in Dean’s lap, hands resting at his sides and he’s snoring, loudly. One of Dean’s arms is slung around Cas’s shoulder, pulling Cas as close to him as possible. His other arm is resting at his side, his fingers gently carding through Sam’s hair, just like he used to do when Sam was little to help him sleep.
Dean is just sitting there with this ridiculous grin on his face, radiating in the strange glow of joy that surrounds him.
He’s with the two people he loves the most in this world and he couldn’t be happier.