Cas had always loved watching people sleep. It was an old hobby of his. People had funny little dreams, and watching them is an easy way to learn things about them. Dreams told a lot, after all.
Watching the Winchesters sleep was still interesting. Their dreams were adventures. Sam dreamt of sex and home and lost love. He dreamt about pretty girls and long car rides and dinners with his family. Sam saw his mother's face and his brother's smile and a girl called Jessica's laugh. Sometimes he saw with Ruby, although those dreams made Cas uncomfortable.
Dean's dreams were different, and much less happy. Dean's nights were mostly blank, but when he did see things, they were terrifying. Dean dreamt of Hell. He was tortured in his sleep. He saw death, mostly. Sam's, Bobby's, even his own. Cas hated watching Dean die most of all. He never made a sound when he slept. He didn't thrash or whimper. His eyelids barely fluttered. He stayed still and stiff, and suffered through whatever came up.
This night was one of his worse nights. Dean just replayed Sam's death, over and over. He would be running to him, close enough to touch him, when the knife plunged into Sam. He would fall into his arms, and Dean would cling to his brother's lifeless body.
When the scene would finally be over, it would start again.
The sun rose early and Dean woke up first, like he always did.
He ran his hand over his face and yawned. "What time is it?"
"Seven twenty-two, a.m." Cas said. He never showed any signs of his nightmares in the morning. Morning was a clean slate. Why stain it with the fears of yesterday?
He rolled over to see Sam in the other bed, still sleeping. Dean smirked. "You know, he sleepwalks when he has nightmares."
"I do."
He sat up in bed and pushed the covers off of him. Dean didn't wear shirts to bed. That didn't make Cas uncomfortable, but it made him feel odd. Sometimes Sam would sleep shirtless, but that didn't phase him much. Sam without a shirt was just Sam without a shirt. Dean without a shirt was a whole other animal.
"Sam." Dean said, getting up and shaking him. "Sam, get up."
Sam's eyes jerked open and he pulled back to hit Dean. It was a reflex at this point. Dean just laughed. "Calm down, Rocky. There's a gas station half a mile down the road, why don't you go get us some coffee?"
"Why don't you do it yourself?" Sam half whispered.
"Seniority. Get up."
Sam begrudgingly got out of bed. Dean pulled his keys out of his pants and threw them at him. Sam caught them in midair without even looking. The brothers were so in synch with each other that they almost shared a brain. They were always like that, even when they were children.
Cas had watched them their whole lives. Dean was taller than Sam until he turned eight and Sam hit his first growth spurt. Dean was jealous, as all little boys would be, but he never showed any signs of it. His only thought was to keep his brother safe, even in elementary school. He was born protective. Cas liked that.
Sam slammed the door behind him and Cas and Dean were alone.
"You know, I think this is the first time in weeks that we haven't had anything to kill." Dean said.
"Good." Cas sighed. "We can relax."
Dean buttoned up a plaid shirt and pulled on his jacket. "Relax? We'll relax when we're dead. We're going to seize the day."
"And how do you plan to do that?"
He opened the curtains of the motel and watched Sam drive off. "We'll improvise."