(Based off of brightfallenstars beautiful picture, post/34304054421/exit-wounds-dedicated-to-wayward-and-graceless-and )
Back when Castiel fell, Dean and Sam were sitting at Bobby's place, just doing some normal research. Suddenly, Cas teleported in. When they saw the vacant look on his face, all three lurched to their feet to try to catch him before he keeled over. Dean made it just in time to keep his friend from falling backwards and probably bashing his skull in.
When he laid Cas down, he was already unconscious. Dean noticed that one of his hands was wet from where he had braced it against Cas's back. Dean rolled Cas over to expose his blood soaked back.
"What in the hell?" Bobby muttered.
Sam crouched down and touched Cas's neck. "Wait, he's warm. Isn't he usually cold? I didn't think that angels had body heat."
Sam and Dean maneuvered the angel so that they could find the source of the blood, taking off various pieces of clothing until they found his bare back.
Shocked at what they saw, Dean lost balance from his crouch and fell back onto his ass. "He didn't. He couldn't have," he murmured, horrified.
"I think he did…" Sam whispered back.
Cas had cut out his own wings. He had become human.
Sam, Dean, and Bobby did their best to stitch up their friend's ruined back. But no matter how many times they had stitched each other up, it had never been this bad. At best, he would have two long scars tracing down his back where his wings once emerged.
"He's just gonna have to take it easy, I guess," Bobby said, watching the still unconscious Cas.
Dean turned and walked away from them, the first of many times to come, to attempt to drown his guilt.
Castiel had given up everything for Dean. He threw away his Grace, even ripped the wings from his back.
He didn't regret a thing, though. Dean was the Righteous Man, he was an amazing hunter, and above all else, he was Castiel's friend. The first true friend he had. He was happy to sacrifice anything and everything for that.
Still… From time to time, when he thought no one was looking, he would flex his shoulders in a familiar way. He still remembered the feel of his wings flaring out, casting a menacing dark shadow. He missed that, similar to how an amputee missed a limb.
Regardless, he still didn't regret it.
Dean and Sam made sure that he kept an eye on the stitches until they were taken out, then they hounded him about not reopening the wounds. He did as they asked, as always.
A few months later, his wounds had healed. Since he had been careful with himself, the only signs of Castiel ever having wings were two thin, white scars.
After a long hunt with the brothers, Cas stepped out of the shower and into their motel room, clad only in jeans.
Dean cast a glance his way when the former angel walked past. He took a drink from the glass in his hand, a small grimace on his face. "Hey, Cas. Your back is looking a lot better."
Castiel stopped, then turned slightly. "Thank you, Dean. I am glad it's healed." Unconsciously, he shifted his shoulders just like he used to.
Pausing, suddenly self conscious, he glanced at Dean's face.
Dean had noticed Cas's movement, Dean noticed everything that Cas did. He stared at the glass in his hand, still a fourth full of amber liquid, and tossed it back.
"Cas…" Dean cleared his throat. "Cas, can we talk?" He glanced across the room at a snoring Sam.
Castiel swallowed the sudden lump in his throat. "Of course, Dean."
Dean stood, and led his friend just outside of the room. "Listen, Cas," he avoided looking at Castiel. "I know-"
"Dean, stop." Castiel interrupted Dean in his commanding angel voice. "I know you're going to apologize or say that you wish you could take back what had happened. I don't care about any of that. I fell of my own free will, and I did it so that I could help you without being restrained."
Dean kept his eyes averted, "Yeah, but I know you miss it. I've seen how you move, like your wings are still there. I know that must suck for you."
Castiel snorts, a very non-angel sound. "Of course I miss my wings. But have you noticed that they're the only thing that I miss? I don't accidentally try to smite anything, do I?"
Reluctantly, Dean meets Cas's eyes. "No, I guess you don't. You don't walk into my dreams, either. Which," Dean grins, "I'm pretty happy about."
Castiel smiles calmly at Dean. "I do miss the wings, but I will always prefer to be here with you."
Dean smiles back at his friend. Suddenly, an idea pops into his head.
"Hey, Cas, how do you feel about tattoos?"
Two days later, Castiel was laying face down on their motel bed, a cool balm being applied to his back.
Cas smiled despite the still-raw feeling that started on his back and trailed down the backs of his arms.
He stood up once Dean finished, and went to look at his back in a mirror. The tattooed wings looked smaller, yet so similar to the ones that he once had.
"Thank you, Dean," Castiel smiled, truly happy. "This is just what I needed."