Sam doesn't understand.

He stands looking at himself in the mirror, hardly daring to blink, occasionally glancing over his shoulder just to confirm that what his eyes are seeing isn't just a trick of reflection, that they're actually there. About the third time he runs his fingers over them, the faint tickle of sensation verifying that yes, they're solid and real and attached to him, he actually starts to believe.

Of course, that's about the time that Dean comes in, flushed and laughing-happy with exhilaration, feathers fluffed every which-way, and catches him "feather fondling," as he calls it. As if Dean hadn't been doing the exact same thing earlier.

When Sam first saw Dean experimentally flexing his new wings, he felt a moment of wonder followed by a surge of blind jealousy. He tried not to show it, though. After everything he's done, everything he's been through, Dean deserves something special, just for him, be it his own personal guardian angel or a golden set of angel wings.

Castiel must have seen it on his face, though. He always could see things Sam would rather keep hidden.

Dean had walked out onto the porch to fully stretch his wings out, gleeful exclamations about wingspan easily heard, when Castiel reached out and gripped Sam's shoulder. Turning him around, Cas ran his finger in two firm lines along his shoulder blades, as if unzipping something.

It started as a tingle under the skin, making Sam shift at the weird feeling growing steadily stronger. He whipped off his shirt just in time for two large wings to erupt forth, feathers sprouting over new-formed skin and bone in a glorious cascade.

They should feel heavy, unnatural. They don't.

Sam still doesn't understand.

Castiel just smiles, unsurprised and pleased, and helps Dean drag Sam outside the cabin they're staying at, isolated enough that three guys with wings won't draw any attention.

Dean takes off with a whoop, bounding a half dozen steps before he takes to the air, looking so natural on his bronze-gold wings that Sam wonders how he ever lived without them. Castiel turns to Sam with a curious look. "Come fly with me?"

Instinctively Sam hunches his shoulders, wings pulling in tight so he can't see them. They make him feel self-conscious, exposed, almost uncomfortably aware of himself in ways that he really doesn't care for. Well, not the wings themselves, really. It's just . . . he doesn't understand.

With a frown Cas reached out and runs a finger along a long flight plume, stroking the silky-soft material delicately. "What's wrong? Do you not like them?"

Sam shakes his head. "No! No, they're . . . they're beautiful."

They are. That's the problem. Cas had explained what the wings were, what they were made of, exactly why they were so natural on two guys born without them. Dean doesn't seem to have a problem going around with his soul exposed on his shoulders, on display, but with wings that eye-catchingly gorgeous, it's understandable.

If Sam ever had to think about it (and he might have, just not in these terms), he thinks his soul should be tarnished, darkened and bloodstained by his actions, his choices, his pride. He started the freaking Apocalypse, for God's sake! He nearly killed his brother and willingly followed a demon, drank her blood until he was addicted, and set Lucifer free, condemning who knows how many thousands of people. His wings should be black as soot, withered and streaked in red. They should be ugly---

Cas touches his wings again, palm of his hand brushing from wing joint to tip, which feels weirdly as if he'd clapped a hand on Sam's neck affectionately. "They suit you."

The wings are dark blue, rich as a summer's evening sky at the bone, gently fading lighter down the pinions to tips edged in pure white, like a pristine sun-drenched waterfall. They remind Sam of a blue jay crossed with a peacock, bright and beautiful and unique, a shimmer of color enough to make the world seem drab.

How the hell does that suit him?

Cas stares at him for a long moment, scrutinizing, before he looks over to where Dean is dive-bombing the lake like an oversized eagle. Dean lets out a loud yell as he misjudges slightly and his boots drag through the water, sending up a spray and overbalancing him enough that he tumbles through the air to crash-land barely on the shore. He rolls onto his back, wings spread beneath him, laughing with delight.

Sam envies his brother that, that despite everything he can still find something to take joy in. He doesn't know if he can do that anymore.

Dean bounces to his feet, stretching and shaking water and dirt from his wings. He looks back toward the cabin with a huge grin and shouts, "Sam, get your pansy ass in the air! It's awesome!"

Dean looks at Sam's wings as if he's seen them all along.

Cas takes his hand, tugging gently but insistently. "Come fly with us." Not a question.

Sam doesn't know if he can do that anymore, and he still doesn't understand. But, as he follows Cas and takes his first fluttering steps into the air, he's willing to try.