A/N: A series of linked one-shots set primarily in the fifth season of Supernatural, tracing the development of Sam and Castiel's relationship from uncertainty to deep friendship. This isn't intended to be a pairing story in the traditional sense, but it is meant to draw as close to that line as possible without stepping over. I hope you enjoy reading.

Note: One of the most tragic aspects of Sam's character, in my mind, is how deeply self-reproachful he is. Perhaps it's because he never gets forgiveness from anyone else, but at some point he almost seems to stop seeking it, to accept the full weight of the apocalypse, Lucifer rising, etc. as if he were the only one who had a hand in it. Anyway, this chapter is meant to address that. It's set at a vague point in season 5, probably after 5.10 "Abandon All Hope" or 5.11 "Sam, Interrupted."

Pairing: Castiel + Sam, light.

.x.

The sun was not even down yet when Castiel found him on the roof of the church.

Sam had noticed the red-brick building the first night they rolled into town. A burnt-out husk, it stood amidst the fields at the edge of the little city in Iowa, bordered on three sides by expanses of black dirt and downed yellow cornstalks snapped or uprooted by the harvester, its red walls aflame with the last of the daylight. Sam had tracked it with his eyes as the Impala raced by, taking in the broken glitter of stained glass clinging to the frames of the empty windows, the paint peeling on the rough wood sign pounded into the lawn that had given over to groundcover, scrub and wild grass conquering the cracked concrete steps. He'd turned his head to keep it in view as they followed the road into town, but he hadn't said anything when it disappeared into the lengthening darkness at their back, because he knew Dean wanted to find a motel and a bar, not necessarily in that order.

It was two days before Sam made it back to the church—two days of sleeping poorly at the town's only motel, scouring all his usual sources in search of the next job, anything to end the layover, keep them moving forward, one step ahead of the things that were dogging their heels, always so close behind them that sometimes Sam looked up expecting to see them in the rearview mirror. Two days of Dean complaining about the beer at the only bar in town, a crumble of lumber under a slanting tin roof, but trudging off in that direction nonetheless as soon as the sky got red. Tonight Sam had walked him to the bar and then just kept walking, down the two-lane road that led out of town, until he reached the abandoned church, and found the lock already broken. In the attic an enormous round window looked out across the endless fields, the glass all gone except for dazzling blue and purple shards embedded in the frame; Sam had hoisted himself out by the eaves and moved across the splintering slate shingles in a crouch until he reached the empty bell tower in the middle of the roof. Then he'd braced one leg on either side of the peak and leaned back against the crumbling tower, staring out at the sun slowly melting into the western horizon, the clouds around it red as blood.

Sam pulled one knee up toward his chest and let his head rock back against the crimson bricks, his cell phone resting in the palm of one loose hand. He would be back at the motel long before midnight, long before his brother; he would never let Dean come back to an empty room.

"… not you anymore…"

The tinny voice emanating from the cell phone speakers almost didn't sound like Dean's, but it didn't matter—Sam knew this message by heart, well enough to fill in the cadence of his brother's tone, all the words that were just a restless mumble with the phone this far from his ear. He waited for the automated voice asking for an action, and his thumb hovered over the nine, the button he always pressed in the end to save the message for another fourteen days—but for now he pushed the four and listened to Dean's voice replaying, a few phrases rising above the hum of early crickets to catch in his ears.

"Listen to me, you blood-sucking freak…" Sam let his eyes wander over the fields, following a flock of birds as it rose from the shining, broken cornstalks. "Always said… have to save you or kill you… fair warning—I'm done trying to save… a monster, Sam. No going back." A breath of wind blew Sam's bangs across his face; he brushed them away and hit the four again.

"You like high places."

Gingerly, being careful of his balance, Sam turned his head to look at the man who had appeared behind him on the roof. Castiel's gaze swept over the view before his eyes dropped to meet Sam's, one pale hand braced against the crown of the bell tower. In the sunset light, his usually plain coat burned like a cinder. Sam sent the angel a small smile.

"Hey, Cas," he greeted, readjusting his shoes in the wedges between the shingles. Then he turned back to the sinking sun, the lowest rim of that brilliant white disc just crumpling against the horizon, less and less blinding the closer it got to the ground. "Aren't you a little early?" he joked.

Castiel frowned. He shifted a step closer and bent down until he was level with Sam, one hand tracing the groove between the dark red bricks. "I didn't realize we had an appointment," the angel said, his voice serious and mildly concerned.

Sam laughed under his breath. "No, we didn't. I just meant… you usually come at night. Late, late at night, when…" Sam hesitated, then swallowed his brother's name, shaking his head and knocking red dust onto the shoulders of his shirt. "When most people are asleep."

Out of the corner of his eye, Sam could see the angel looking at him, a thoughtful crease bothering his forehead. "I come when you are troubled," Castiel said simply. His piercing gaze burned against Sam's face like a physical touch. "The nights are difficult for you," he added in a murmur.

Sam looked down at his jeans. His hand tightened around the dark face of his cell phone, but he kept his jaw set and said nothing, and Castiel let him be, too accustomed to Sam now to expect a response. For a long moment the only sounds between them were the gathering crickets and the metallic mumble of Dean's message repeating, the angry lifts and barks of feedback audible even through Sam's muffling fingers. Then the automated voice was back, louder than the message itself, eternally asking what he intended to do.

"To delete this message, press seven. To save it in the archives, press nine. To hear this message again, press four." Then came the silence, the world holding its breath, waiting for him to make a choice.

Castiel shifted beside him, the red and gold light playing across his face. "What is that?" the angel asked, gesturing to the phone with one hand.

Sam curled his fingers into a loose fist. "Nothing. Just a voicemail from a while ago."

Castiel studied him for a moment, taking his face apart feature by feature as if he'd heard something unexpected, some evasion, in the tone of his reply. Sam tried to smile but the expression got stuck at the corners of his lips. Then the angel reached out and wrapped his hand around Sam's, lifting the phone into the space between them, and the pressure of their joined fingers made the buttons light up. The screen flickered on again, counting the seconds of the looped recording.

"…to hear this message again, press four…"

Castiel pressed down on Sam's thumb. As Dean's voice spilled into the air around them, banishing the serenity of the vacant rooftop, Sam wondered if the angel had pushed the volume up, too—the words stung in his ears, louder than they had seemed in a long time.

"Listen to me, you blood-sucking freak."

Castiel became very still. Sam tore his eyes from the phone and cast his gaze out across the mown landscape, fixing on a speck moving in the distance: a silver pickup tearing down one of the access roads between the empty fields, a cloud of golden dust roiling up from its tires. The particles ignited like sparks when they hit the horizon.

"Dad always said I'd either have to save you or kill you," Dean's voice told him again, brittle with rage. "Well, I'm giving you fair warning—I'm done trying to save you. You're a monster, Sam—" Castiel's hand almost seemed to flinch around his. "—a vampire. You're not you anymore. And there's no going back."

The message cut off abruptly, leaving an unsteady silence that eddied around them, moving in patches like the wake of a boat that had departed too soon, unbalanced on the water. Sam pushed nine with the corner of his thumb. As the automated voice chirped, "Message saved for fourteen days," Castiel released Sam's hand, letting it sink slowly back into his lap. Then the angel rocked back on his heels, his body perfectly still in spite of the slope of the roof, slightly hunched as if his coat had become too heavy.

"Why are you keeping that, Sam?"

Sam shrugged one shoulder against the red brick tower. His shirt rasped over the mottled surface, tiny threads catching and pulling into fuzzy clumps. He thought suddenly of the pile of discarded laundry lying at the foot of his rented bed, his and Dean's clothes, the load he'd meant to throw in the motel washing machine before heading out for the night—but Dean had already been slipping his shoes on, and Sam knew he wouldn't wait. The sun was below the horizon now—all that remained were the thin layers of vivid clouds, glowing like they had snared scraps of the sun before it shed its molten skin on the precipice, dropped over the cold, dark edge. The truck was gone, too.

A warm hand flitted against his arm. "Sam."

"It's nothing, Cas," he replied. His voice was even in the first shadows of the long autumn twilight, as quiet as the crickets that were picking up their instruments in the grass below, their song drifting up to the roof like the ring of a distant telephone, going unanswered. Castiel edged forward along the spine of the shingles until he could catch Sam's eyes. The young hunter sighed. "It's nothing, really. I'm just… not ready to delete it yet."

Castiel's eyebrows drew together. The frown settling over his lips said he wanted more, a clearer explanation, but Sam just shook his head, turning back to the fading sunset. There was so much that the angel didn't understand at the simplest of times—it seemed impossible to explain that he had listened to that message on a park bench in the sunshine, in a gas station bathroom as Dean picked through the premade deli sandwiches, that sometimes he turned off all the sound and let it play in the darkness of their hotel rooms, staring at the seconds ticking by on the glowing screen of his cell phone, knowing by heart when to press nine again, to keep it saved. That it didn't hurt him at all to listen to that message, but somehow he needed to feel it—the sensation that buzzed in his ears whenever he hit repeat. It felt like throwing a rock as far as he could across a still pond and then sinking with it into the deepest part of the water. There was something down there that he needed to get to.

Castiel was still staring at him—Sam could feel the intensity of that gaze on his face—and he gave a short laugh, an incredulous smile overtaking him. "It's just something I'm hanging onto for a while—seriously. I don't even listen to it that often," he said, lifting his head to meet the angel's eyes again. "Really. It's fine, Cas."

The nickname was light on his lips, and Castiel's shoulders relaxed just barely under the fall of his trench coat. But the angel's gaze stayed where it was for another long moment before dropping to the phone in Sam's hand, all five fingers laced tight around the screen of black glass.

"That message was not from Dean," Castiel said at last, his expression thoughtful.

Sam straightened against the bricks of the bell tower, turning to face the angel fully for the first time. He braced one hand against the collapsing red stone behind him and the roughness of the mortar line between bricks seared his fingers. "What are you talking about?" he asked.

Castiel extended his arm and ran one finger down the phone's dark face, pausing when he reached Sam's whitened knuckles. "When Dean was being held by the angels, before… Lilith…" The pause was barely an inhale, but somehow it echoed over the roof like so much more than a moment of silence. Castiel set his jaw and turned his hand over, smoothing his thumb across the underside of Sam's. "Zachariah said he needed to give you one more push, to ensure you would break the final seal." The angel's hand tightened around his, and Sam stared at their overlapping fingers, chaotic and convoluted like the veins in a heart. Castiel shook his head. "I never knew what he meant by that. Now I do."

Sam took a deep breath. It felt like it took forever for that inhale to reach his lungs—like it had to climb down every rung of his spine before finally sliding into the center of his chest, pushing out on his rib cage. He looked out across the fields as the soft breeze stirred at their backs, cold as a shiver as it blew through the arches in the bell tower and unsettled the film of dust on the slate shingles. The first star was glimmering in the pale pink western sky, pulsing like oncoming headlights or a distant lighthouse, the only port in a sunset storm. Sam let his exhale go.

"Wow," he said.

Something was glowing inside of him—probably relief, he thought, that whatever they'd said to each other before or since, these words at least hadn't come from his brother, these words that had been ringing in his ears as he'd stepped into the hallway of that convent, onto the road to Hell, armed with his good intentions. But even as the overwhelming feeling stole through him, banishing the chill of the autumn breeze, something pulled back equally hard—some impulse that constricted his fingers around the cell phone, pressed the black plastic into his palm until he could feel the headphone jack leaving a blister on his skin. He swallowed against the dryness in the back of his throat.

"Well," he said at last, shrugging once more. "Then it really doesn't matter."

Castiel pulled his hand carefully back to his side, but his eyes never left the darkened screen. "You didn't know," the angel realized, his lips tight. Sam said nothing. The darkness of the early evening was surrounding them now, creeping up the old red walls and over the edge of the roof as Castiel shook his head. "You never asked him about the message."

"Cas…" Sam broke in. He left the rest of the explanation unsaid; Castiel could probably fill it all in for himself at this point. Sam closed his eyes against the twilight, concentrating for a second on the throb of his own heartbeat—but he blinked them open a moment later when quiet fingers touched his face, mapping the depth of the hollows beneath his eyes. He stared back into pensive blue irises.

"How much have you been sleeping?" Castiel asked. The question was so soft that it almost disappeared, whisked away as soon as it left his lips by the subtle breeze, flooding them with the scent of dry leaves and turned dirt and the sharp coldness of night, waiting in the wings. Sam would have ignored the question entirely if the angel's gaze hadn't been boring into his.

"Enough," he said. Somehow the single word made him unbelievably tired, so exhausted that if he hadn't been leaning against the bell tower he thought he might have slipped bonelessly down the side of the roof and slumped to the ground below, nothing but a skid mark on red brick and slate. Then suddenly there was a hand on his, waking the cell phone again, one finger pressing hard against the voicemail button.

Sam blinked. "Cas, what're you…"

"Please enter your password."

The automated voice was shrill in the air between them, repeating the request when neither hand moved for a few long seconds. Castiel watched him as though waiting for Sam to do something—to enter the code or to stop him, Sam wasn't sure—and then the angel turned his gaze to the phone and painstakingly entered 3-3-2-6, each tiny chirp from the buttons as loud as a train whistle in the silence—his childish password, so simple even Castiel could figure it out. The message started up again—Zachariah's message, Sam knew now—and somehow underneath the familiar voice he thought he could hear it for the first time, all the ruthlessness and cunning that made Zachariah the thing he was most afraid of seeing in the Impala's rearview mirror. And somehow, in spite of all of it, something inside of him lurched when Castiel covered the seven with his thumb.

"Listen to me, you bloodsucking freak—"

"Cas, wait—"

"Message deleted. End of messages."

Sam inhaled and held it. Castiel slowly withdrew his hand from the phone, leaving an impression of warmth wherever their fingers had crossed—but he kept his steady gaze on Sam's face, waiting as the young man's eyes took in the glowing screen of his cell phone, the timer clicking meaninglessly on now through the automated settings loop, finally rising to meet the angel's only once the buttons had gone dark. Then Castiel shook his head, a simple motion that was somehow so full.

"I think you've listened to that message enough."

Sam dropped his eyes to his lap, swallowing to get rid of the feeling that had crawled up from his stomach. Castiel tipped his head to one side. Then the angel shifted and settled his back against the bell tower, matching Sam's pose and stretching his legs down the roof's spine, his shoulder coming to rest against the brick just beside his companion's head. To Sam he looked like some immutable statue—a stone angel lounging on top of an empty church, his gravel voice quiet as the dusk.

"I swore to Lucifer that I would never let him have you, Sam."

Sam's head turned at the words; he kept his expression neutral but his eyes swept over Castiel's features, fighting to read every line by the light of the early stars. The angel looked back at him, solemn as ever. Then Castiel lifted one hand to push Sam's hair back behind his ear, his fingers lingering for a moment in the dark brown strands.

"I am barely an angel anymore, and what power I have left is so much less than what I have lost—but I would die for you, Sam Winchester. I will kill for you. And I will not let Lucifer into your mind… whatever form he takes."

The last of the light was gone from the sky now—darkness had taken over, and the stars were breaking through in clusters, mirroring the lights of the little city away across the fields, a knot of brightness in an otherwise dark world. Sam looked up and scanned the velvet blue dome for constellations. He'd known a lot of them once, when he and Dean had tagged along on their dad's camping trips and had crawled out of the tent at midnight to search the sky, his older brother always eager to one-up him in picking them out. Now the only one he could remember was Dean's favorite: Orion, the hunter. He glanced over at Castiel and wondered what the angel saw when he looked at the sky. Then he let out a heavy exhale, and reached out to touch Castiel's hand, pressing his palm over his companion's rough knuckles.

"I have to leave soon," he whispered, wondering whether he was telling himself or Castiel. "It's a long walk back."

Castiel turned his hand over underneath Sam's and squeezed. "I will take you back, when it is time."

Sam thought for a moment about Dean sitting in a beat-up chair in the rundown bar, bottles lined up like bowling pins in front of him, and considered telling the angel why he wanted to get back. But somehow he had a feeling that he already knew. So he just turned his body toward Castiel and laid his head against the angel's shoulder, pulling his knees up until they rested half across Castiel's lap. He closed his eyes and felt an arm wrap around his back, holding him up against the gravity of the slope.

"You should ask him about it," Castiel said, just a voice in the darkness now, his fingers steady in the folds of Sam's shirt. "The real message he left you that day."

Sam shook his head softly. "I can't do that, Cas," he murmured. He slipped his phone back into his pocket and then buried his suddenly empty hand in the liner of the angel's coat, the beige fabric soft as corn silk on his skin. He breathed in the scents that always lingered around Castiel, clean water and candle smoke. "As long as I don't know for sure, it could have said anything. It could have said that… he forgives me."

Castiel rested his cheek against the top of Sam's head. "You are long forgiven," he whispered back.

Sam knew that he couldn't believe something like that. But somehow, nonetheless, those words made him warm all the way through, and he leaned into Castiel's embrace with a little smile on his lips, content to let someone else hold him up, just for a moment.

.x.

Thanks for reading. I'm glad some people are liking this story.