Spoilers: vaguely up to season 5.

Notes: Title comes from T.S. Eliot. I realize I'm about six years late getting into this fandom but better late than never.

i.

"Don't you ever get tired?" Sam asks one night. He doesn't know if he's dreaming anymore, because even if he closes his eyes, he's always opening them again somewhere.

Lucifer stares from across the room, the skin he has claimed as his own is angry with blood. It runs down his cheek, but he doesn't seem to notice. Sam wonders what it could feel like to not even be aware of your own physical vessel, too busy with fire raging constantly inside.

"I'm an Archangel." Lucifer says, like he's bored already. "What would be the point? Tired. It's such a human thing, Sam."

"But, how? How can you be so angry all the time and not feel tired?" Sam asks himself more than the devil, because it doesn't seem like something angels would exactly understand.

Lucifer smiles, "I'm not angry, Sam. I mean, sure, Michael is a pain in my ass and my Father abandoned me, but I've had time to deal with my issues. I've had so much time. You can't even fathom it."

"Then why don't you stop? Stop being... the devil?" Sam isn't afraid to look Lucifer in the eye anymore, because even if he could rip Sam apart with a blink of the eye, he won't.

"And ask for forgiveness? Hope for salvation?" He grins, "Because, I know what salvation is. I know what it means to love to the point of destruction, Sam."

Sam thinks about love and he sees Dean, and Jess, and a mother he never even knew. He thinks about Ruby. He closes his eyes and when he opens them he's back in some shitty motel, with Dean snoring in the bed next to him.

He wonders if he'll go to Hell for sympathizing with the devil.

ii.

The Impala is about the only home Sam has ever truly known, and he's memorized every scuff in the interior. He remembers his Dad's strong hands gripping the wheel, looking into the rearview mirror to check on his youngest son. Then one day, without warning, it became Dean's hand running across the leather, no one in the backseat left to check on.

"What do you think Dad would say if he were here?" Sam looks at Dean, who looks so perfectly content in the driver's seat.

Dean glances over, "About what? This whole vessel for the devil bullshit? I doubt he'd tell you to sign yourself up for possession by Lucifer, Sam."

Turning back to look out the window, Sam sees his face reflected in the glass and he doesn't see any of John Winchester left.

Dean doesn't get it. He wonders if anyone ever will.

iii.

Sometimes Sam dreams of Dean dying. He's seen Dean die in so many ways thanks to Gabriel that he's surprised his brain can concoct new scenarios to play out. They get more and more ridiculous: Dean's head gets stuck in a blender, a coconut falls out a tree and kills him, he gets struck by lightning.

The one he always comes back to is Dean's neck under his foot, so vulnerable.

"There's a point to all this." Lucifer says, staring down at the older Winchester's lifeless form sprawled in the grass.

Sam can taste blood in the back of his throat, sweet and sticky.

"You might be able to kill your own brother, but that's the coward way out." He spits back, the smell of death filling his lungs.

Lucifer's face remains impassive, "Maybe that's the point."

iv.

Dean doesn't say anything about Sam's dreams, he pretends not to hear the moans and gasps in the middle of the night coming from the bed next to his own. He sees the growing circles under his brother's eyes. He watches Sam's soul die slowly, choked out of him by something he never had a chance against.

"You want to let him in." It isn't a question, Dean knows Sam better than he knows himself, he knows that in the end Sam would always want to be something he couldn't be.

"I'm tired." Sam says and lays his head back against the hard headboard in the shitty motel for that night.

Dean goes to get their bags and when he comes back Sam is snoring lightly.

v.

"Could you even stop being the devil if you wanted to?" He's used to sharing his nights with Lucifer, and he's not sure what that says about his soul. "Or is this like some predestined thing?"

Nick's body is fraying around the edges, tearing apart like some shirt made of the cheapest fabric. Sam thinks he could've saved him by just saying yes. He wonders what his body would look like - little tears everywhere perhaps. But Sam's held evil before, he doesn't think it would hurt so much the second time.

"Think about everything you've learned about God, and then ask yourself that again." Lucifer inspects his hands, hands which once had felt things so pure and perfect Sam thinks it would've burned him.

"You can stop being anything." Sam's stubborn jaw juts out beneath his dark hair and Lucifer steps closer, straightening the collar on Sam's jacket.

"Oh, Sam. You know better than anyone that isn't true." He backs up, but his breath feels warm on Sam's face. "I've seen inside your brain. You think what I am is beautiful."

In his heart, he knows it's true - Lucifer is an Archangel. He is powerful and intelligent and merciless, and sometimes Sam wishes he could be too. He wants to feel that power inside his own body, as sick and wrong as it is.

Maybe there's a reason he's the chosen one as Lucifer's vessel.

He's the only one who could learn to love the devil himself.

vi.

"Okay. I'll do it."