Burn all of your bridges just so that you can build them again with thicker ropes.

Hurt all the people you love and then commit every felony to win them back.

This is the art of living with a ticking heart.

This is how I destroyed you. And this, is how I kept you alive.

-SHINJI MOON

Sometimes Sam wonders if it is the demon blood in his veins that allows him to lie to Dean. If it casts a sort of protective invisible barrier between the two of them. Ever since they were kids, it had been near impossible for Sam to hide anything from his brother. Dean saw through him with frightening ease.

It wasn't because they shared the name of Winchester. Wasn't even because, up until a few months ago at least , they had the same blood flowing through their veins.

It was just because they were Sam and Dean. And for Sam, more than anything else, it was annoying as hell.

After all, he had perfected the innocent look by the age of twelve. As a child, it had come in handy, mainly in obtaining bigger portions of food from tired middle aged waitresses. One lazy blink upwards, a quirk of his head to the side if he really want to rub it in, and his plate would be piled high with fries. Dean loved it, thought it was the most hilarious thing in the world until Sam started using it on him. And then he became more wary, at times studying those large hazel eyes like one might a loaded gun.

These days, Sam restricted its use to stubborn police captains and grieving parents. But Dean was different. He knew the tells that Sam swore he didn't have. Learned them, memorized them, could write the fuckin book on them.

Which is why he was intensely grateful that Dean isn't looking at him now, especially since Sam is halfway convinced he's about to burst into flame.

There's this ghost. There's always a ghost but this one was the daughter of a preacher. That had snagged Dean's attention to the point where the bad puns from his brother reached new heights.

Or rather lows.

Sam didn't even spare him the cursory forced laugh or rolled eyes- couldn't- because there were so many ways this could go wrong. The first and foremost being Sam stepping onto hallowed ground and turning into a large pile of Sam ash.

He hadn't been surrounded by four walls of stained glass since before he started drinking blood. And by now, he doubts there's anything except demon running through his system. So, of course they have to go inside a church because the universe hates him. It's a written law out there somewhere, like gravity, that Sam and Dean Winchester do not get breaks.

He'd spent the entire day trying to come up with a halfway decent excuse that Dean might buy, but no such luck so here he is, sweat dripping from his brow, trying to think up a prayer that might convince God to allow his presence in a holy place, just this once. And if not-access denied. Then Dean would know. Dean would see.

Sam feels his heart pick up inside his chest, fights the urge to turn and run far away.

He hovers near the entrance, pretends to glance around, to scour the area. Dean thinks something bad might have happened here, something that turned a dead girl into a ghost. Sam's mainly left the investigating to his brother these days. He pretends to research, drags up enough information in twenty minutes that he can pretend took all day to find.

It's difficult, near impossible, for Sam to focus on things like newspaper articles and autopsy reports anymore. Partly because the blood in his system turns the world into a shattered sort of kaleidoscope that he needs to piece back together little by little. Partly because his temperature has risen four degrees and his heartbeat has doubled, keeping pace to that Metallica song that Dean puts on repeat.

But mainly because there's Dean. Dean to protect. And so many things that he needs protection from. Swallowing demon blood was not unlike removing a blindfold. And Sam could actually see, feel, taste all the evil out there. And while Dean isn't defenseless, might punch him for daring to think that, it still only takes one bullet, one defense dropped, one second too late, and it's all over. Again.

Besides, Dean can't feel demons, not like Sam can. A blip on his radar, a silent tug somewhere in his chest when one creeps too close. Dean doesn't need to know, doesn't need to worry. Because Sam is finally strong enough to keep them all away.

Strong enough to keep Hell from latching its claws into Dean again. He imagines how it felt when Castiel tore him away, the shudder that ran through the pit. The loss.

Sam and Hell both want Dean with something akin to desperation. But Sam knows that he'll be the one to keep him. It's taken longer than it should have but he's learned the price it will take to keep Dean safe and he'll pay it, gladly.

Snoring, bitching at him for buying rabbit food, smell of motor oil and leather seats. For as low an opinion as Dean has of himself, his brother is the last person in the world who deserves to be damned. Sam is already dirty, has been tainted since birth and there's nothing to do about that now. No Hail Marys. No absolution. He can kill other evil, hope to restore some sort of balance, a payment for what he is, that he exists at all but even that is a stretch, wishful thinking.

Dean calls his name, a slight edge of impatience and Sam realizes he's been hesitating at the door still, a somewhat stricken expression written across his face. He smells blood, even now, even here, and he realizes it's just because he's bitten his lip.

Sam shuffles forward, whole body tensing, waiting for the pain, for the burn. He wonders if he might be able to jump out fast enough to prevent full body decomposition.

And then goes boneless with relief when seconds tick by and nothing happens. So relieved that he isn't even aware that Dean is giving him a scrutinizing look as he staggers to one of the pews, rests his head on the worn wood in front of him. Because maybe this means that Sam isn't as much of a monster as he thought.

There is a brief rustle, so loud in the quiet of the church and Dean is tipping Sam's head back, brushing messy hair from his eyes so he can lay his hand against his forehead. Sam trembles at the cool touch.

"You have a fever."

Sam just nods. The demon blood inside his veins turns his body into a furnace. He's lucky that Dean hasn't noticed before now.

"Sammy, look at me."

Sam is powerless against that and blinks up at his brother even though it's clearly a bad idea. Dean writing the book on him and all that.

"Your eyes are dilated too." And there's that crease of concern that Dean wears on his forehead like a second skin.

"Flu maybe." he rasps out, a quick shrug of shoulders.

"Well fuck Sammy, gettin kinda feeble in your old age, huh?"

It earns a smile from Sam just like it was meant to.

"You shouldn't curse in church." Is all he says, still focused on the smell of Dean around him, the gentle brush of calloused fingers through his hair. Sam knows he should push away instead of leaning towards it. Dean isn't into chick flicks moments like these and only puts up with them when he thinks there's something seriously wrong with Sam. Something worse than a flu. If Sam was in the right mindset, he'd push him away. But he doesn't. Just tilts his head and closes his eyes and soaks up Dean's presence. Better than morphine.

They find and burn the bones. Salt and fire. And blood too. Lately, Sam's nights always end in blood.

It's almost midnight. Time gets better and worse for Sam after the clock strikes 12. Just a few minutes to go and Dean is trying to fight off sleep, has been for the past two hours. Sam barely resisting the urge to just knock him out with a clean right hook, send him sprawling into unconsciousness so he can get on with it already. But that would kind of defeat the purpose of all this.

His skin is starting to itch, deep down where he can't scratch it, bones shaking in their casing.

After they'd gotten back to the hotel- a hole in the wall that resembled every other hole in the wall they'd stayed in, Dean had shoved pills down Sam's throat and covered him with at least three blankets, snapping at Sam to shut up when he brought up the goal was to lower his temperature instead of increasing it. But Sam had let him because Dean needed to take care of Sam. Needed it like breathing.

Some warped thing in their biology, something that clicked in the wrong place in Dean's brain when Sam was laid in his arms as a baby in front of a burning home. Take care of Sam. And Dean had, always.

Sam watches Dean's chin dip further and further towards his chest. He already knows how this night is going to end. So he stares at Dean and tries not to think of what God might think of him. After all, God knows why he's doing what he is and isn't God supposed to care about that things like that? He did allow him on hallowed ground after all. And even if not, Sam still can't bring himself to stop. Can't stop picturing the deep bloody grooves all along Dean's stomach and neck from the hellhounds. His cocky brave stupid brother ripped nearly in half.

And yeah, usually there are rules, moral codes to follow, things you just don't do no matter what. But this is Dean and Dean is different. There are no boundaries, no lines he wouldn't cross- something he's discovered recently. And maybe he really isn't Sam anymore. It was something that he had thought on long and hard, how much blood he'd have to drink to shift the balance. For him to become more of something else.

Eventually Dean falls asleep to the droning commercials in between a Star Wars marathon. Sam slips from his bed, turns off the TV and allows the room to settle into silence. Dean shuffles a little, dipping lower into the mattress. Sam lays a blanket on top of him, imagining the taunting Dean would subject him to if he were awake. But it's the middle of winter and the heater in their room is barely clinging to life and it might die while Sam is gone and what then? A small part of his mind realizes that he's blowing this all wildly out of proportion, that the worst that might happen to Dean is getting a cold.

But it feels serious. Feels like Sam doing penance, giving a part of his body over as payment, abandoning a piece of himself behind.

It always feels dangerous when he leaves Dean.

Sam triple checks the salt lines, cuts his hand to draw a sigil with his blood on the window that he'll wipe off before Dean wakes. He'll be gone an hour at most. Knows Dean will be safe but it still feels all kinds of wrong leaving his brother sleeping in bed. As close to defenseless as you can be.

But he'll drink his fill tonight, keep more stored in a canister for later.

In a week, he'll have to go out and do it all over again. He'll have to leave Dean alone, repeat his atonement. But for now, for a little longer, his brother will be safe.