Hi guys! So this is my first fanfic in...well a lot of years. Supernatural and the SPN Family have inspired me to get back on the horse.

This is a one shot set within the Season 5 finale 'Swan Song' when Lucifer takes over Sam. I thought it would be interesting to see what happened between Sam and Lucifer 'internally' and this is the result!

Enjoy!

"Yes."

Sam's stomach roiled uncomfortably; the vestiges of demon blood sloshing around, making him nauseous. The rest pulsed through his body and roared in his ears, nearly drowning out the high pitched buzz beginning to resonate throughout the room.

Nearly, but not quite.

Lucifer knew. Their plan wasn't a secret anymore. It doesn't matter, Sam thought, fighting the quieter voice that wrapped him in doubt. If he knew, could Sam beat him? He swallowed the panic that bubbled up inside of him, shooting a quick glance at Dean before the high pitched buzzing grew louder and a blinding light pierced through the darkness in the room. Dean's arm darted up to cover his eyes as he staggered back. Sam's fists clenched at his sides; his eyes squeezed shut. The demon blood, now surging through him as his heart banged almost painfully against his ribs, felt like it was boiling. A shudder raced down his spine despite the heat inside him. His head throbbed; the pulse in his temples felt like his veins were going to burst. Lucifer forced his way in, pushing and crushing Sam whose breath left him. It was as though they were stuck on a ledge when there was only room for one.

Sam teetered on the edge precariously. He pushed back, hard. The demon blood continued to roar, but the light from Lucifer was too great. Too much. Pushing back with everything he had, Sam grappled for control. A laugh echoed, hollow and victorious. He couldn't hold on.

With horror filling him, Sam felt his footing on the ledge slip.

No.

"Sammy!" Dean turned and grabbed Sam's arm, trying to yank him to his feet. The wind from the portal scraped and snapped around him, blowing fragments of rubbish across the room. The cold bit at his fingers as he latched onto Sam's jacket, tugging him towards the hole in the wall. "You've got to go. Now!" Sam's groans rose above the window, his face contorted in agony.

What have we done? Dean thought as he pushed Sam again even as every fibre of his being cried out at what he was doing - sacrificing his own brother. "Go now, Sammy. Now!" He was going to lose his brother. Intentionally. He had let it get this far and now they couldn't go back. He watched, guilt and dismay warring within him, as Sam stepped towards the hole.

And stopped.

Sam blinked and looked around him. Stared at the cold, solid walls of Bobby's panic room. It was different though; the demon wards were gone, leaving the walls a plain rusted red – the colour of old blood. The circular fan in the ceiling was gone, replaced by a single lightbulb which swayed softly from side to side. The furniture was gone except for a two chairs sat in the centre with an old television set stood on a rusting cart.

"I won."

Sam spun around quickly his hands clenched into fists at his sides. Lucifer stood with his arms crossed in the open door, leaning against the frame, a satisfied smile tugging at his lips.

"No – you haven't." Sam growled, lunging towards Lucifer. This was his mind – he would be damned if Lucifer was stronger than him here. His arm was raised, hand clenched in a fist, the beat of the demon blood screaming through him as he launched himself at the devil. Lucifer sighed and flicked his fingers lazily. Sam shot back, grunting as he slammed painfully into the chair which didn't move.

"So bold, Sammy. But you're a little bit too late." Lucifer chided softly. "Uh uh." He admonished when Sam tried to rise. He flicked his fingers again, sauntering towards Sam. Straps snapped up out of the arms and legs of the chair, securing themselves tightly around Sam's wrists and ankles.

"No!" Sam growled, clenching his teeth and glaring as his struggled against the restraints. "You said a fair fight! You call this fair?"

"You had a chance when I started taking you over. You just didn't realise that was your only chance."

"You lying son of a bitch! Let me go!" Sam shouted, his chest heaving with every breath.

"I never lied, Sam," Lucifer replied as he circled around behind Sam. "I just don't always tell you the whole truth." The TV in front of him flickered on, revealing the portal. The edges were cracking further, breaking shards of plaster and wood off before sucking them into the darkness. The blasting gale resounded through the speakers; the sound was clear but tinny, as though it was coming from far away

"What is this?"

"The outside. I thought you might want to see what I see. Now shhh and watch as I destroy any hope your brother has left."

"No! You can't-" Sam was immediately cut off as Lucifer gagged him, tying it tightly around the back of his head. He winced, groaning as he struggled against his bonds. Looking around, he saw that Lucifer was gone. Dragging his eyes back to the TV, Sam could only watch helplessly as the screen filled with the image of Dean's concerned face.

Lucifer rotated on his heel, a slow grin, unlike any Dean had ever seen on Sam, spreading almost apologetically across his face. Lucifer shrugged nonchalantly and clasped his hands.

"I was just messing with you," he confessed. "Sammy's long gone."

Despite the gale blowing through the room, Dean's breath evaporated from within his lungs. Abject horror shot through his veins like ice. No. Sam was meant to be stronger. He had said he could win.

Inside the panic room, Sam struggled violently, screaming that he was there – he wasn't gone - but the words were muffled by the gag. Tears pricked at his eyes as he saw the fire die in Dean's. His brother thought he was dead. They had lost.

Dean barely even registered as Lucifer chanted again, closing the portal and removing the rings. If Sam was gone, there was nothing left. Nothing he could do. Everything they had fought for was worthless. He sucked a breath in heavily, blinking hard, once, lifting eyes that were blurred with tears.

Lucifer was gone.

The screen had gone blank what felt like hours ago. Sam sat perfectly still inside his mind; his eyes focused on the door in front of him. Struggling hadn't worked – there was no way he was getting loose. Instead, he concentrated on the empty chair beside him. The demon blood, mixed with his old psychic abilities, were the only things he had left at his disposal. The chair shifted and scraped, shuddering under the intensity of Sam's glare. He pushed harder until finally the chair flung itself at the door, ramming it. He grunted in satisfaction; he wasn't useless. Renewing his concentration, he continued to slam the chair against the door.

"Sam." Sam jumped as the voice echoed from the TV set in front of him. "I can feel you…scratching away in there." He cast his eyes towards the screen again, but it remained blank. The door creaked open. Lucifer walked in with an almost apologetic smile on his face. Sam glared up at him. "Look, I'll take the gag off, ok?" He moved behind Sam, speaking as he undid the gag. "You got me all wrong kiddo; I'm not the bad guy here."

Sam jerked his head to the side as the gag was removed, venom in his gaze.

"I'm going to rip you apart from the inside out. Do you understand me?" He snarled, his body trembling with anger. Lucifer picked up the chair from where it had fallen beside the door.

"Such anger…young Skywalker" he mocked as he turned the chair so that he could sit and face Sam. "Who are you really angry with? Me? Or that face in the mirror?"

"I suppose this is all one big joke to you, huh?" Sam retorted, tugging his wrists against the straps. Lucifer's smile faded.

"Not at all. I've been waiting for you for a long, long time," he replied, his eyes fixed on Sam's. "C'mon, Sam. You've got to admit it; you can feel it, right?

Sam stared at him in confusion. "What?"

"The exhilaration." Lucifer leaned forward over the back of his chair. "And you know why that is? Because we're two halves of a whole. M-F-E-O. Literally."

Sam looked at him, appalled. His whole body vibrated with the anger that simmered like lava below the surface of his skin. He looked pointedly at his restraints. "This feels pretty damn far from good."

"I'm inside your grapefruit, Sam," Lucifer spread his arms wide, grinning, deliberately ignoring Sam's look. "You can't lie to me. I see it all. How…odd you always felt. How out of place in that…family of yours. And why shouldn't you have? They were foster care at best. I'm your real family."

"No, that's not true." Sam spat through gritted teeth. He was pretty sure that if he had control of his physical body, he would've cracked a tooth by now.

"It is." Lucifer said quietly, his gaze almost sympathetic. He got up from his chair and circled around Sam. "And I know you know it. All those times you ran away – you weren't running from them – you were running towards me." He hunched down over Sam's shoulder and brought his face close to the side of his head. Sam flinched, leaning away. "This doesn't have to be a bad thing, y'know. I let Dean live, didn't I? I want him to live. I'll bring you folks back too." His voice dropped, almost to a whisper. "I want you to be happy, Sam."

"I don't want anything from you!" Sam growled, tears pricking the backs of his eyes as he stared straight ahead. He could almost feel his own fear and hatred radiating.

"Not even a little payback?"

Sam glanced sideways at Lucifer who was still hunched over him. "What's that supposed to me?"

"Look closely." Lucifer instructed nodding towards the TV screen. Sam shifted his gaze; the screen was no longer blank. Instead, it showed a group of men and women stood silently in a circle. The light above them was dim, casting half the room in shadow. Sam squinted at the screen, leaning forward slightly to see who they were. "None of these little devils look familiar to you?"

"That's Mr Bensman…one of my grade school teachers" Sam murmured, recognition finally sinking in. He concentrated on the other faces as Lucifer moved away from him.

"And that's your friend Doug from that time in East Lansing. And Rachel…your prom date." Lucifer stood in front of the screen, spreading his arms wide and smirking down at Sam who stared up at him, brows furrowed. "Sam Winchester – this is your life! Azazel's gang: watching you since you were a rugrat – jerking you around like a dog on a leash." He leaned in conspiratorially, an excited glint appearing in his eyes. Sam recoiled. "I know how you feel about them. Me too. So what do you say you and I blow off a little steam?"

Before Sam could reply, Lucifer was gone again. An odd sensation tingled throughout Sam's limbs. Since being in the panic room, he had known that what he thought was physical sensation was imaginary; he wasn't in his corporeal body. This was different; he could feel. He could feel his body walking forward, the slight tickle of his hair against his forehead, the steady rhythm of his breath. Yet it wasn't his breath. It was Lucifer's. He watched in horror as he saw his hands grab Rachel around the throat on the TV but felt his hands grasp her warm skin. He felt her pulse beating frantically against his palm as she looked up at him with fear in her eyes. He felt the steadiness of his own heartbeat even though it should've been hammering. He felt the bones snap in her neck as he jerked her head sideways.

He could feel it all. But he couldn't move. Couldn't stop it.

"Are we having fun yet?"

So what did you think? Reviews always welcome!