Cas has shy wings. He'll fold them up tight next to him or duck them under his arms when he thinks someone is coming too close. He'll hide them away when they meet anyone new.
But, when Dean has a terrible night and he's sitting on the floor, Cas sits next to him and slowly, slowly lets them unfurl, just ghosting around Dean's frame like an umbrella. It's so close and Dean can't help himself. He raises a shaky finger and brushes one of the feathers with it. Involuntarily, Cas's wing flutters back with a whoosh and Dean thinks he's hurt him. When he looks at Cas's face, the angel has his eyes closed and he's biting his lip.
Dean opens his mouth to apologize, but when he does, he realizes that Cas's wing is still slowly coming closer. Closer. Dean watches, mesmerized as the tip of the wing dips and brushes, feather soft along his arm, Cas's hands in fists as the angel breathes out.
Dean touches Cas's hand in reassurance watching it unfurl. The muscles in the sides of Cas's eyes relax and finaly, he lets them blink open.
The two men are close, foreheads touching, holding hands. Dean holds perfectly still when he feels the wing tentatively wrap around his arm, slowly tightening. It's intimate and he can see Cas's lips twitch with tiny shudders Dean doesn't fully comprehend, and he knows. Knows Cas has never done this.
So, they stare, the feathers fusing to Dean's skin, their breaths heating up the tent that's created under the giant blanket of wings, one over their head now as the space between them gets smaller and smaller. And Cas's fingers tremble with every miniscule twitch Dean makes, even as the hunter tries to stay achingly still.
Cas's breaths are fast, his hair wild, his eyes bright even under their shadow of black.
Dean's out of breath, too, simply from watching Cas come undone.
Then, leaning forward as slowly as he can manage, Dean kisses him chastely, noting the way that Cas's lips are soft too, in a different way, the movement of their mouths together small, but desperate as Cas's wings tighten around them with a growl.
Dean doesn't know when it happens, but suddenly, he's holding Cas, the angel's head against his chest, his eyes closed. He looks exhausted and small.
Lightly, Dean kisses the top of his head, tasting a little fluff of hair between his teeth.
"Thank-you" Dean whispers, and he feels the flutter of wings against his skin.