Dean Winchester loved to cuddle.
That realization almost made Cas's jaw drop, because the angel already loved to cuddle- like, a LOT.
When Cas had first come to Earth, he thought that the idea of cuddling was strange. But once he got used to the concept of hugging, and body language; it all made sense. And Cas slowly became a little desperate, determined to feel what being close to someone like that was like. That was why he always invaded Dean's personal space- he wanted to be as close to him as possible.
Cas also went from being utterly confused by hugs to needing them all the time.
When Cas and Dean started dating, Cas loved to cuddle with Dean. The hunter found it ridiculous at first- how the angel would sprawl out in Dean's lap if they were watching TV, and he'd never move.
How he'd wrap his arms around Dean at night, and snuggle closer to him just because he could.
How he'd purposefully walk closer to Dean so that their hands would brush against each other.
Dean would smirk and roll his eyes at the angel, but he'd never turn down the prospect of Cas cuddling with him. Hell, it was impossible to say no to him, especially when he crawled into your lap like a lovesick puppy that demanded to be petted.
"Cas, why do you love cuddling so much?" He questioned one day, playing with Cas's hair as they sat lazily on a couch.
"I like it because I get to be as close to you as possible, and you are a very comfortable human being." Dean had laughed.
But Cas had assumed that Dean didn't really care for cuddling- he just accepted it because Cas loved it so much. Cas discovered, however, that he was wrong.
They had been staying in a cheap motel room while Sam and Dean worked a case, but Cas had some things to do while Dean and Sam went off on their FBI work. Cas wanted to get an early start, so as soon as the sun came up, and rolled off Dean and reached for his trenchcoat.
He was met with a sound that could only be described as a whine coming from Dean. The Winchester rolled over, wrapping his arms around Cas's waist and tugging sleepily at the angel.
"Dean," Cas insisted. "I have things to do."
"They can wait." Dean mumbled, pulling Cas back on the bed so that he was lying down.
"Dean, I have to-"
"Shut up, Cas." Dean said sleepily, rolling over and snuggling into Cas's chest. The angel paused.
"Dean-"
"Just stay here and cuddle with me, huggybear." Cas's heart melted.
"I thought you didn't like cuddling."
"Shut your mouth- I freaking love cuddling. You're like a baby koala." Dean leaned closer to him, and Cas looked at him in surprise, but didn't try to move again.
Instead, he snuggled closer to Dean, ever the little spoon, and was content to stay in bed with sleepy, cuddly Dean.