Castiel stands on shaky legs, listing to the side, feet sliding on the ground. The weight of this body, this body that was never his (not completely), is new and foreign and he can feel the heightened awareness of his true form seeping away, like rainwater on parched earth.
There is still Grace inside him, those few tendrils that clung to his vessel when Metatron–
He can hear his brothers and sisters, screaming in his head, hear the whistling of them overhead as they pass, wings aflame as they Fall. They're crying out, frantic voices in his mind (fading, fading, fading too fast), calling for their Father and Castiel can do nothing but watch, nothing but stand there in this body that is now his and watch because the weight of failure settles deep in the very marrow of his bones.
The heavy weight of his disintegrating wings is nothing compared to the crushing pain within.
Because he had not Fallen, not like the others now streaking the sky, their wings torn by the ionosphere, the smells of burning ozone.
Metatron had set him down upon earth, and bid him farewell and now–
He can feel his wings deteriorate, no longer congruent with this human body, the angelic form dying quickly inside and it hurts, like nothing has ever hurt before, amplified by the shrieks he can hear in his head and outside of it.
Castiel can feel that the wound at his side has re-opened and he stumbles forward, to do what he doesn't know, doesn't know, and did he ever?
He watches. Watches the comets overhead sail past him, strike the ground in furrows and in craters, moving earth and concrete and grass.
All of them, every last one Falling.
They will be reborn, he knows this. Like Annael, they will be reborn and never remember, never know that they were the Firstborn, the first children of God, the first he abandoned and left behind to their destruction.
But Metatron has placed him down, and Castiel will remember and the knowledge of it all, the millennia and the utter infinity, overwhelms him in unceasing waves until he thinks he will fall to his knees.
And then, there's a pair of voices in the back of his brain, he can barely hear them in the cacophony but he would recognize the brothers anywhere.
Metatron has set him down close to the chapel small mercies;
"Something wonderful is going to happen, for me and for you. I want you to live this life to the fullest. Find a wife, make babies…and when you die, and your soul comes to heaven, find me and tell me your story… Now go."
He pools the last of his strength and flies one last time.
One last time, one last thing, one last deed, one more…
Dean wishes, irrationally, that he could shield his brother from this.
He remembers when Sam was little, remembers the way he used to pray every night, how he teased him for it, every time Sam clapped his hands together and bowed his head. Remembers their father, mocking Sam for believing. Remembers arguing with him bitterly that night, because if Sam wanted that, just that, that one thing, why shouldn't he have it?
God and faith don't exist, Dean. It's better that he learn early on that there is no one out there watching out for him, or for anyone. Just family. No guardian angels or any of that nonsense.
They look up at the sky together, Sam half supported by his arms and the Impala.
The angels, all of them, every last one, are Falling.
Something in his gut, something primal and old, twists and he wants to turn away, wants to close his eyes but still he stares at them crashing to earth like falling stars.
A sound behind him startles Dean, vaguely like the flapping of wings but more like the crunch of dry detritus underfoot, the breaking of old wood and brittle bone.
Castiel almost falls to the ground as he staggers forward and for a moment Dean is speechless, too much going on in his head, in his chest and heart.
Sam calls his name in a rasping voice and Cas just settles his hand on Sam's chest.
Sam glows orange-red again and Dean almost pulls him away, and then Sam's breathing eases and he stops shaking and Cas looks at him, "the last," he informs, voice wavering and rough.
And then he's stepping back and Dean reaches for him when it happens. When Castiel finally falls to his knees and a scream, wild and undiluted, is ripped from his throat.
Fire arches across his back, illuminating at last the wings that Dean has only ever seen in shadows.
They're a slate gray, speckled with blue and white, like sapphire and stardust, smudged with black, splotches of ink on paper.
Dean and Sam see that much, behold for a few seconds before the wings are engulfed by fire, burning white hot and Castiel continues to howl, hoarse and high-pitched and Dean wants nothing more than to make it stop, make it stop, please, make it all stop.
When it ends, Cas falls forward, dropping onto his hands, and Dean's breath catches in his throat and Sam grips his brother tight, can no longer bear to look upward and see the destruction.
Cas feels the pavement, rock and dirt, dig into his palms, getting underneath his fingernails, tiny pinpricks against his skin.
The night sky above returns to near darkness, a pitch black peppered with rain clouds as thunder rolls and lightning falls upon the earth.
"I'm not wrong. I'm going to fix my home."
Castiel calls within his mind, a loud and desperate, pleading wail,
Brothers and sisters I have failed you
I'm sorry, I'm sorry, I'm sorry, please, forgive me,
And is met with a profound and immeasurable silence.