A/N: Spoilers for Swan Song. I've tweaked the ending a bit, but mostly this falls in line with the episode.

Time is…fluid. It starts as a trickle; widens to a delta.

And finally: A river.

An ocean.

This is how Time begins.

Not many can claim to have seen this, but I have stood upon Time's shores and watched Time beat its first waves upon the world and I have listened to its first breaths, its drawn-out sighs.

My Father made Time and then he created Man and Man discovered hate; Man toppled civilizations over its head and warred among itself and then inflicted upon this pure and perfect world my Father shaped within his hands something called a 'Paris Hilton'.

And still my Father loved them, and sent his faithful sons and daughters of heaven to watch over them.

For a thousand years, I sat, and I watched. For a thousand thousand years, I walked among them, seeing but not seen.

Humans are…monotonous. Creatures of habit. I am an Angel of the Lord and I drain time between my fingers like sand, I have that much of it.

But humans are obsessed with trapping it, containing it: They are insects in holding patterns, endlessly circling through these routines, these habits; they seal it away inside machines that tick on their wrists and tock on their walls, but they can never hold onto it indefinitely. They believe, in their arrogance, that they can bend Time to their will, that it will flex and unravel and eventually shred itself apart around them.

But I have seen.

For a thousand thousand thousand years I have seen.

And I understand Time marches only to its own drum.

These seconds that spin faster and fall away into minutes beneath our feet and keep on tumbling into hours- they are an illusion. Time does not speed up nor does it slow down, and I understand that my final day is not any shorter or longer than any other day within my very long existence-

But I look at you, and I wonder.

Time, you bitch, I think, and this is something else I have to thank you for, this…sensation.

You would call it…regret, I believe.

"Cas? You ready to go?" He looks at me with his human eyes in his human face, this man I have the honor to call 'friend', and something inside of me reaches out for him, and if I am not mistaken, something within him reaches out for me too.

It's not…tangible. It is…a charge, a humming: Man is interconnected, tied one to another to another, and when I dove deep beyond the souls of Hell, swam down and down and down to find this one man, to touch his hand, to tow him with me back beyond the surface, I was bound into this web.

I was caught.

I think of dominoes, strange little black cubes with little white dots imprinted down their sides, and the way they sway, and topple, and when one falls the next does as well.

I saw a boy once, playing this game: Building his domino houses meticulously one by one by one, spending hours shaping them just right, arranging them just so with his careful white fingers.

And then with a flick of his wrist, he obliterated them all.

Humans are like these domino houses: impermanent, clumsy, and when one falls, they take another down with them.

Once I did not understand this.

Once I did not call Sam and Dean Winchester my friends, and I did not understand this.

"Cas? You with me?"

God, in all his infinite wisdom, created beauty, and he created it in your face, Dean Winchester, in the slope of your eyebrows and the faint spiderweb of lines beneath your eyes, and once I did not understand this either. This…hold humans have on one another. You are noisy, messy creatures; you hurt one another for no reason. You maim and you kill and you destroy without cause, and you have yet to apologize for the Paris Hilton...abomination. I knew my Father had not been mistaken in creating you, but I could not comprehend his love for you.

And then you were Chosen, Dean Winchester, and you named me family and you rebuilt me when my love for my Father broke me into pieces and you showed me how to choose.

You led me down another path.

And I'm sorry, Dean, that I do not understand lying either, that I have not learned how to convincingly imitate it.

"You can't save Sam," I tell him.

His jaw tightens. He clicks his eyes away from me.

Dean Winchester, a man of few words.

This, at least, I have always understood.

"He's not dying alone, Cas. I can do that, at least. I can be there for him."

I feel…

I feel compression. A squeezing inside of me. I think…I think this is what humans know as heartache.

I smile.

I did not know, before the Winchesters, that a smile is many things: it is an offering, a gift; a joke between friends; a touch without fingers between lovers. Sometimes it is frail, and it breaks; sometimes it says many things, without saying anything at all.

But it is never wasted.

I look into the human eyes of this boy who is my friend, and I say "Yes."

I say 'yes' because I want to, and Dean Winchester taught me this too: That acceptance does not have to be a yoke, a chain to bend a neck beneath its weight; that, when given freely, it can be utterly weightless.

I wish I knew how to use this device you call a 'camera', Dean.

Today is my last day on earth, and I do not know where fallen angels go.

I only know that you will be taken from me. You will be blown away by eons, buried beneath dunes that pile not sand but Time across your back.

In a thousand years, I will not know your name.

So snapshot me. Freeze me away inside your human devices, and always remember that once an Angel of the Lord , who loved his father, who was loved by his father, looked down upon you and found you worthy.

He loved you more.

I step outside.

I breathe the world inside of me.

To be a human is to marvel.

I have watched the world a thousand thousand thousand years, and I have not noticed the way the ground is patched with lace on winter mornings; how it gives beneath my feet as I walk; the way my breath smokes itself into cirriform spirals against pale metal skies.

Fall is cinnamon dust in the air and the smell of burning things and children carving snow angels down through piles of flame.

"Well, let's get this show on the road. Ain't got all day, you know."

They are waiting for me, these friends of mine, and there is beauty in them too, in a dirty old trucker hat and oil-stained fingers and the way they lean on each other, without moving at all.

A boy and a drunk and a fallen angel all walk into an Impala…I think this is the beginning of something Dean once told me, something called a 'joke'. I did not laugh. It was not funny.

But I ask to hear it again.

"No no no, Cas: It's 'A preacher, a rabbi, and a teacher all walk into a bar…'"

It is still not funny, but I listen anyway.

Five hundred years ago, I walked among a library. I knew the things inside of it were called books and I knew they each had something to tell me, but I had never been interested in their words before.

I do not know why I was then.

An older brother once told me there was nothing to see, that he had tried these things called books and that they were empty: not of words or ideas, but of meaning, of purpose. God was purpose and humans understood nothing and these things called books changed none of that.

I sat and I read the library in one day and I did not understand how these tiny single-spaced words held such power over humans, how they incited revolutions and inspired great love and felled entire cities.

But I do think…I yearned. I wanted to understand, to know why these frail little ants called Man felt so deeply that they conjured up the words for these feelings and wrote them down, so that others might feel them too.

I did not read again until Dean Winchester was Chosen, until he left me alone in a hotel room nursing something he called a 'hangover' and went away to find something that would make all the little men with hammers stop nailing things into my brain. He tossed me something called a 'magazine' and advised me to 'take it in the bathroom' if I felt the need to 'pull anything out' and then he walked out the door, shaking his head. I did not understand what I was supposed to take into the bathroom nor what I could pull out of my vessel's body without harming it, but I looked at this 'magazine', and I noticed more of these words in small print beside human women doing sinful things with their unclothed bodies, and I read.

On the night when I understood at last that my Father had abandoned me, I discovered that a woman named Jessica Jiggles liked washing her dishes in something called a thong; that she enjoyed men with large wallets (how big could a wallet be, and still fit inside these things called pockets, I wondered?) and even larger…I believe the word is one I am not supposed to repeat; that she worked part-time at 'Fellatio Hospital', as something called a 'candy stripper'.

I asked Dean what a 'thong' was when he came back, and how candy could be stripped, and why medical professionals would base the name of their place of business off the Latin verb "to suck."

He sat down and laughed until he cried, and told me I was not supposed to read the articles.

I did not understand what was funny, but for the first time in my very long existence, I understood the term "laughter is infectious", and I smiled, and when my smile did not go away, I laughed.

I laughed until my eyes stung and this stinging ran itself down my face and into my mouth where it tasted of salt, and when my vessel's broken eyes stopped leaking, Dean Winchester smiled at me, and it was at that moment I realized something inside of my vessel was broken as well, because it clicked itself back into place.

You taught me to choose and then you taught me to laugh and I wish, my friend…I wish I could go on remembering this forever.

My brother looks at me with Sam Winchester's soft human eyes and I am suddenly tired.

I am old.

I feel all the weight of centuries upon centuries piled on top of my shoulders, and I think of Time, its inevitability: I think of shores being washed clean of footprints and humans swept out to tide, sucked down to flounder and drown among decades, and these two human boys who are my friends and this old drunk who is their father look to me for guidance, and I have none.

I see Sam's struggles beyond the wall Lucifer has erected inside of him, and I see Dean's pain, and I take it inside of me, all of it, and if feeling were incendiary, I would explode with it, combust.

These boys deserve better my family deserves better why can't we have peace-

I have watched my family tear itself apart and put itself back together and gnaw away at the threads that have not been patched back up quite right, and I am so tired of it-

Centuries ago, a son loved his father too much and he rebelled; he fell from grace, and an eon later, another son who loved his father met a human who taught him that blind obedience is not love, and he too fell, stumbled down along a similar arc, a parallel trajectory, and he landed so hard it trembled the earth underneath him.

It broke his understanding of everything.

But I am not Lucifer.

I did not fall in bitterness, away from love.

I fell into it.

"Dean," I say.

He does not look away from Sam.

I do not expect him to.

His name will be my eulogy.

You cannot die without being born, but I was not born: I was Created. My Father reached into Heaven and assembled me from all the best pieces of it, and he nudged all the parts of me into perfect order, until I was just right, and then he Named me Castiel, his Righteous Son.

But it was Dean Winchester who gave me life.

This is blasphemy, I know.

But my Father taught me only to obey: He taught me obligation and duty, to not speak unless spoken to; to love thy Father and honor thy family.

He did not teach me that some family members are not worth honoring. Dicks, is I believe what Dean would call them.

He did not teach me that love is a choice, that it is the best kind of choice: That it will both shatter you and glue you back together; that only once you are broken by it, can you be built into something whole.

I shake something out of my coat and into my palm, and I hold onto it for a moment.

For a moment, I hold onto everything.

If you capture a moment just right, you can slip between seconds, impale yourself there: You have not outwitted Time, but you have persuaded it to give you a reprieve, for just this one moment that stretches out and out and out.

I exhale.

My reprieve is over.

The ground is once more solid beneath my feet, and the air is full of burning things, and here the cinnamon dust in the air is in the trees, holding on, clinging stubbornly.

I know the feeling.

"Hey, assbutt!" I yell, and lob this something in my hand toward Michael, wing it past Lucifer's shoulder, and I see, out of the corner of my eye, Dean mouth this phrase, test it out on his tongue.

He seems bewildered by the texture of it.

Michael flinches, cries out.

He is sucked away into a void I cannot see.

And Lucifer turns on me.

"Castiel, did you just Molotov my brother with Holy Fire?"

My mouth is all ash. I roll it around against my tongue, and I think of laughing in a dark motel room with Dean Winchester and the first whiplash feel of a bond breaking, a tether snapping, and I think about how I have never known fear, or regret, until I looked into the eyes of these two human men, and called them my friends.

I am eaten away by it, this thing called fear: rubber limbs wrapped in liquid muscle.

"Uh…no."

"No one dicks with Michael except me," Lucifer snaps.

He brings two of Sam Winchester's callus-scarred fingers together, and he clicks them.

Dean…

I do not know where I am going, or how long it will take me to get there.

I can only think of you, as hard as I can, in this fine split-hair sliver of a moment before I am disassembled, taken apart down to the atom.

Undone.

I do not pray. I have never needed to: God loved me and he talked to me and whenever I had need of him, I had only to reach out, to call for him.

A prayer is a…letter. A dictation. You throw it out there and you hope someone hears but you never know- you are not sure.

Maybe your voice has been lost among a million others, buried beneath their collective weight.

I pray now. Move on, Dean Winchester. Say good-bye, Dean Winchester.

Let go.

Love your brother and honor his choices and go home to a woman and a boy who will save you.

You have been the savior often enough.

Thank you, my friend.

A/N: I may have made a slight canon goof near the end, when Castiel refers to speaking with God. After I wrote it, I suddenly had the thought that he stated in an earlier episode that he had never actually spoken with God. I ran this past my sister, who said she remembered Cas mentioning that he had never actually seen God, but that she couldn't remember anything about him not even speaking with God. So if this is the case, I apologize for my misstep, and just pretend I wrote something really profound and actually in line with canon. Thanks for reading.