** Context: Season 5: Finale, immediately after conversation where Sam makes Dean promise to leave Sam in Hell and lead a normal life without him – last line of that scene: "You go lead some normal, apple pie life, Dean. Promise me!" **

Dean said nothing, but after a few moments he gave a tight, angry nod. Sam saw the shine of dammed tears in his eyes.

Silence fell. Sam turned his gaze on the road ahead and for a while he absently watched the white lines as they disappeared under the bonnet of the Impala. A couple of times he opened his mouth and took a breath, but the subject he wanted to raise remained stubbornly lodged in the pit of his stomach. Half formed opening phrases flitted through his mind, and images gathered around them, memories tantalizing and ephemeral as ghosts.

He glanced toward Dean and found himself gazing at his hands, his fingers curled around the steering wheel. His focus moved up the bare forearm to the point where the cuffs of Dean's shirt folded over his elbow, up to the curve of his shoulder, and finally resting on his face where the attention became fixed on every detail of it. This would be Sam's last opportunity to marvel at those features, that remained incorrigibly boyish despite the years and the cruel experience they'd endured, at the light stubble Dean always sported to draw attention from the almost feminine sensuality of his soft full lips, from those wide multi-hued eyes and their impossibly long lashes.

Dean caught Sam's eyes for a moment, frowned briefly, then returned his attention to the road. "What?" he asked.

Sam couldn't answer. Neither could he drag his gaze from his brother's face.

Dean glanced at him again, out of the corner of his eye, and shifted in his seat. Sam knew he was making him uncomfortable but still couldn't help himself. Last time. Last chance, he reminded himself. He must speak now.

Was it his imagination that there was a tension building in the silence that was more than simply awkwardness, more than just the tightness that was growing in his own thighs, or the heat prickling his skin. Was Dean feeling it too?

"What, Sam?" Dean demanded again, this time with a distinct edge in his voice.

Sam drew a quick breath. "Dean, would you pull over for a moment?"
Dean gave him a hard look, half suspicion, half concern. "What's wrong?"
"Dean, just – just pull over would you? Please?"

Another searching look then Dean steered to the side and off the road. "O.K. Sam, what's eating you?

Sam glanced back at Castiel. This was an awful thing to do to him, but . . . He reached back and shook his knee. "Cass? Wake up, Cass."

Castiel stirred then woke abruptly, his intense stare focusing instantly on Sam's face. "What is it?"

"I . . . need to talk to Dean for a minute . . . alone."

"What?" Dean interrupted, incredulous.

"I just need half an hour – quarter of an hour – ten minutes . . ."

Castiel's expression never changed as his eyes bore into Sam's for long moments. Then he opened the car door. "Take all the time you need," he said, and was gone.
"Are you out of your mind?" Dean cried. "We're in the middle of nowhere! He doesn't have his powers. Where's he going to go?"

Sam's heart was racing now, his breath coming fast and hard. "There's something I need to ask you, Dean."

Dean looked wary now. He turned his attention frontward and appeared to study his own fingers as they traced nervously around the rim of the wheel. "O.K. Spill it."

"Dean . . . all the years we've been doing this – all the things we've hunted, demons we've ganked . . . you know there's something we never . . . confronted . . ." Sam watched Dean's jaw tighten. "In that motel, Dean, outside Rivergrove"

"I can't believe this!" Dean interjected, so quickly it was clear he'd anticipated where Sam's thought was headed. "You're going to bring that up now?"

"Yes, Dean, now! Of course, now!" Sam's voice was hoarse with emotion. "I have to know - "

"It wasn't me, Sam."

Sam reeled physically. After everything that had gone down between them, the blunt denial was like a blow to his gut. For a few moments the wind was knocked out of him. Then the fire of anger burned in his veins. A frown creased his eyebrows and forehead, and his nostrils flared. "Dean, don't do this to me," he croaked. "Not now. Not tonight . . . I don't know what happened to you that morning, when it started, but we both know how it ended. I let you inside me, Dean. I gave myself to you completely. You must know I wouldn't have done that if I hadn't known, if I hadn't been a hundred per cent certain, it was you!"

Dean's lips were pressed tightly together. He was still staring at his own white knuckles.

"For fuck's sake, Dean," Sam pleaded. "All the years I had Azazel riding me, then Meg and Ruby . . . I didn't have any choice then – or I thought I didn't . . . and tomorrow I'm gonna give my ass to Lucifer . . . are you gonna let me do that thinking - " Sam swallowed, tried to bring his voice under control. "Are you going to sit there and tell me what happened between us that night was just another demon making me his bitch?"

The sound of Sam's ragged breathing made the silence loud.

"Dean, please!" He hesitated, searching for words that didn't sound trite, but could only think of the obvious. "This is my last . . . our last . . . Oh god, Dean, you've got to give me something!"

Dean's arm was trembling. Still tight lipped, he gave the briefest nod, then another. Then he suddenly opened the car door, got out and slammed it behind him.

The sound of the shutting door numbed Sam's body. Tears were beginning to sting at his eyes when he heard the rear door open. For a moment he thought Castiel had returned before Dean's voice startled him.

"Well, are you joining me back here or not?" he demanded, bluntly.

Sam turned swiftly and stared at Dean. His eyebrows were arched challengingly, half mocking, but in his eyes Sam saw the trace of a mute appeal that revealed he was only half as sure of himself as he was making himself out to be, but it was enough. Sam almost fell out of the car. His legs felt so weak they barely supported his weight and as he tumbled into the back beside Dean his heart was hammering against his rib cage.

It was awkward at first, as if neither of them had ever had sex before. They both reached for each other at the same time and got in one another's way, their arms knocking so that Dean wound up slapping Sam's jaw and Sam nearly poked Dean's eye out, but then Dean took charge. He grabbed Sam's wrists and drew him forward until their foreheads touched. They were so close they were sharing the same quickened, trembling breath, and their lips were all but touching. There was a pause, like the moment when a pearl diver stands at the edge of the cliff before plunging into the ocean. Sam waited, and ached, and waited

. . .

There was barely room for them both. It was difficult and constricting. Their limbs jutted out at awkward angles and jabbed into each other uncomfortably. Dean's foot was twisted painfully against the far door, and Sam's head was pressed against the ashtray. The toy soldier he'd jammed in there so many years before now dug into his temple. None of that mattered. It was never meant to be easy. Sam understood that now. It was always a struggle for them to be together, but in those rare, far flung, painfully brief moments when they were perfectly together, it was perfect. And it was the memory of that moment that bound them even when they were at their furthest extreme from each other. Always, when it mattered most, Sam would remember.

. . .

Dean reached for a blanket from the back shelf and drew it around them both .Wrapped together in that protective cocoon, sheltered from the cold and the oppressive darkness Dean could almost believe that this was the one place where he could keep them safe, inside this metal frame that was the body of their world.

"You know, this was a first for me, Sam?" That little crease of a frown appeared between Sam's eyebrows and tugged at Dean's heart. Would this be the last time he saw that? "I've never done it in the Impala before," he elaborated.

Sam's eyes widened. "Seriously? You've never brought a girl here?"

Dean shook his head. "Thought about it once or twice, but it didn't seem right somehow. This always seemed like . . ." He searched for the right words.

"Sacred space?" Sam suggested.

Dean laughed softly. "Trust you to put it that way." But he loved him for it. "Have you ever . . . ?"

"No." Sam assured him. "No, of course not."

Dean tightened his hold on Sam, pulled him closer, and Sam reached for his hand and knitted their fingers together. It couldn't last forever though. Time was pressing on them now. Dean could feel its icy breath on his neck. He checked his watch.

"What time is it?" Sam asked.

"It's late, Sammy. You should get some sleep." He was still calling him Sammy when he'd sworn he was going to treat him like a grown man now.

Tomorrow.

Tomorrow Sam would be a man. Tonight, now, for one last time, Dean needed him to be Sammy, needed to take care of him this one last time. He combed his fingers gently through his brother's hair. "Go to sleep, Sammy."

"What about you?"

"I'll be fine. Go to sleep."

Sam closed his eyes and suddenly all Dean could see was the youth in his features, and he was swallowing on the emotion that rose in his chest and throat. He continued to stroke Sam's hair and after a few moments he found himself murmuring an old lullaby. His voice was husky and barely carrying the tune but he persisted and, after a while, he realized something miraculous had happened: Sam's breathing had slowed to a soft, steady rhythm. He really was sleeping.

Dean continued to watch his sleeping brother for a while longer, but a line of grey on the horizon heralded the approaching day and he knew they had to get moving. He extricated himself from the embrace as gently and quietly as he could, gingerly picking out his clothes from the tangled heap on the floor, and retrieving his shoe from the back shelf, afraid that at any moment he would disturb Sam's fragile rest. Sam slept on oblivious, the sleep of the dead, and the gathering chill constricted Dean's chest.

He was praying in spite of himself: God, give me strength. God, give me strength. God give me strength. He was so afraid. So afraid that when the pit opened he would cling to Sam with his dying breath and let the whole fucking world go to hell around them so long as he could keep Sammy in his arms for even one extra moment. But the only thing that killed him more than the thought of letting Sam go was letting him down. God, give me strength. God, give me strength. God, give me strength.

As he stepped out of the car the cold hit him like a blow. He dressed as quickly as he could but was still shivering uncontrollably and his teeth were chattering as he climbed into the front, then he caught something in the corner of his eye turned his head and almost leapt off the seat.

"NGUH!"

Cass was already sitting in the passenger seat.

"Wh – how – where – how did you – how long have you been back?" Dean demanded.

"I've been here a while" the angel responded staring stonily at the road straight ahead of him.

Dean's lips parted. How long? he wondered. The heat of shame prickled his skin then, abruptly, it was replaced by a hot defensive anger. "If you're sitting there judging us, Castiel, you have no right. You could never understand -"

"I'm not judging you, Dean." He turned his piercing eyes to stare directly at him. "And I do understand."

Castiel's gaze was so intense that, for a moment, Dean remembered the angel's former power and imagined he could feel it burning into him.

"For what he is about to do, your brother needs all his strength. And so do you."

A sudden sharp breath filled Dean's lungs and left him in a shuddering exhalation. Was it possible that Cass truly did understand? Was he giving them his blessing?

"We should be moving. We still have some distance to travel," Cass reminded him. Dean stretched for the car keys with trembling fingers, but the icy morning wasn't reaching him any longer. Something inside, neither warmth nor cold, but deep and vital was shielding him. As quietly as he could, he turned over the ignition and the engine of the Impala growled to life. He glanced anxiously at the back seat but Sam didn't stir.

"We should let him sleep while he can," Castiel acknowledged.

Words tumbled out of Dean's mouth before he could stop them, before he even knew what he meant by them. "Angels don't sleep," he said.

** This is an edited version of a story already posted on the Sam/Dean Slash Archive site. The full version is too explicit to meet the rating requirements of this site but may be viewed by googling the slash archive and searching for stories by fanspired. "The Last Memory of the Impala" is the 3rd story in The Personal Demon series. **