Since returning from purgatory Castiel has noticed a few things. One; that it's difficult to get Dean to settle down just to sleep. He keeps fidgeting, or playing on his laptop, and it upsets the angel.
Sam will sleep soundly, lulled into a false comfort that Dean will settle on his own. The angel knows he won't though.
Pushing into the hunter's space he takes the laptop from him, setting it on the table. He ignores Dean's hushed protests as he begins to work the other out of his clothes, down to something more comfortable. Even if he would have to lay down himself, he would get the hunter to go to sleep.
Father above Dean could be a pain.
He kept tugging at the hunter's jeans, even as Dean kicked at him, "Cas?! Cas what the hell are you doing?" it comes out as a hushed hiss, looking frantically over at Sam before back to the angel who successfully had the other down to his underwear.
A brow is cocked at the sight of the pink, satin, lacy panties but he makes no comment. He just pushes Dean back onto the bed before stripping down to his own underwear. With that done he crawls into bed behind Dean. A little wrestling occurs, the hunter likely mistaking what Cas' intentions are but he settles with a pout as the angel holds him to his chest, kissing his forehead.
"You're an ass…" his fingers trace over the scarring on Cas' chest as the other smiles against the skin of his forehead.
"Hush. I had to get you to sleep somehow. We both know you need it. So just get comfortable. I will be here in the morning."
Then within the circle of Cas' arms Dean rolls around to find some place he was comfy. Cas was not surprised it was facing Sam but at least it left Dean curled with his back against the angels chest, easing into a light sleep.