A/N: For right now this is just a one-shot, but maybe it'll turn into something more. Who knows? But this was an idea I had after watching the season 12 finale, so I just had to write it. It's been kicking around in my head for a while.
TRIGGER WARNINGS: Allusions towards rape.
Sam was washing the dishes when it happened. As he'd been putting a plate away he heard him, a voice in his head. I'm not dead, Sammy.
The plate fell from his hands and crashed to the floor as his body went slack, fear rising up from within the previously dormant black pit in his chest. He didn't even hear the plate shatter about his feet, the only sounds palpable to him being that of the blood rushing in his ears, and the voice replaying in his mind.
The cold, calm surety the words had been spoken with caused his insides to go numb, and he was vaguely aware of his body heating up. That voice – he'd heard it more than any other in his entire existence, and the teasing way he'd said Sammy caused dread and horror and disgust to travel outwards from his stomach, consuming all they touched.
Shivers ran rampant through him, and his chest and stomach began to ache. He managed to galvanize himself into action, and Sam ran for the bathroom. He luckily got his head over the toilet just before he began to puke. Spasms took over his body as it violently emptied itself.
When he finished he collapsed onto the floor and wiped at his mouth with his sleeve. Another shiver passed through him and his heart was beating madly against his chest, as if it was trying to escape from the fear living and breathing within him.
No. It couldn't be. It just couldn't be.
But it was. It was him.
Lucifer.
Sam didn't even question how he'd gotten into his head. He'd been able to do it over a year ago from within the Cage due to it being damaged. If he could do that while still locked up, Lucifer being free meant he could do so much more.
It shouldn't have been surprisingly really. But it'd taken him by surprise, shocked him to his core. He hadn't expected it. Hadn't even considered that something like this might happen.
Some part of him had hoped he was safe with Lucifer locked away in another dimension.
And then he started thinking of the person who was locked away with him: his mother.
Before Sam could even think about what he was doing, he climbed out of the depths of his own terror to ask, Is my Mom all right?
His entire body tensed as he lay there, awaiting an answer. Minutes dragged on, and still the black pit within him didn't weaken. Horror was running rampant through his veins. Horror because Lucifer could get in his head. Horror because his mother was with him.
Oh god, he didn't even want to think about the things the Devil was surely doing to her. Sam knew all too well how Lucifer was when he got mad.
His body began making an excess of saliva and his stomach twisted in on itself, threatening to make him puke again.
When no answer seemed forthcoming Sam forced himself up off the floor. He took off his flannel shirt so that he was only in the gray t-shirt he'd been wearing underneath, and then he washed his hands and face with cold water.
Usually cold water could help calm people down, but at that moment it had the opposite effect on Sam. Cold, biting, just like Lucifer's touch. Just like the knives he'd used to tear into him. Just like every single day within the Cage. Freezing, sharp cold.
A sob made its way up from his throat, and he gripped the edges of the sink as he bowed his head.
He had to snap out of this. He had to.
But he couldn't.
Everything hurt. The memories, the anxiety about his mom, the wilting, blackening fear that lived in his soul.
And then, he heard his voice again.
You know she's not.
It took him by surprise again and it took a few seconds before he was able to breathe.
Sam tentatively reached out for that place in his head where he felt Lucifer's presence, and he asked, What are you doing to her?
Do you really want to know?
Sam had to swallow back bile, and sweat trickled down the sides of his face.
Seconds passed, a minute, two, three. And Sam hadn't replied. There was nothing to say, nothing to do. There was no escape, nothing to be done. At least not now.
He had to get his mom back. He had to save her. He had to get her away from Lucifer before he could…
What if it was already too late?
What if he'd…?
He had shown an interest in her.
Oh god, oh god, oh god, oh god.
And then Sam started dry heaving, his arms shaking as he held himself up, leaning heavily on the sink. Blood came out of his mouth, and what he didn't manage to spit when his body calmed a little dribbled down his chin. He cleaned his face again, using warm water this time.
Sam, I've already told you so many times. God can't do anything. He doesn't care.
There were warm pinpricks at the corners of his eyes then his tears started falling, rolling down his cheeks, and he sobbed.
Hey, Sammy, wanna hear a fun fact? Lucifer asked, his voice filled with jubilant amusement. No? I'll just tell you anyway. He waited, trying to have a dramatic pause. His next words hurt, not just emotionally, but physically as well. Your mom doesn't scream as loud as you.
A cry left Sam, Lucifer's voice now hurting his head. Each word had felt like a hammer tapping against the front of his skull.
His deceptively charming laugh sounded in Sam's head, and it felt like a knife was running along his spine, his whole body tingling.
Please… Sam begged. Leave me alone.
Silence. Then: Fine, I'll just go entertain myself with your mother. One Winchester is better than no Winchester.
Wait! No! No!
What? he asked, sounding thoroughly irritated.
Don't.
Aw, Sam. How cute. But you know I'm just going to do whatever I want with her. And I can do whatever I want in your head.
N-no.
I'll be seeing you later, bunk buddy.
His presence in his head left, and Sam collapsed onto the floor where he huddled up and continued to cry. He cried till his diaphragm hurt, cried till he couldn't breathe, cried till he began to feel dizzy from dehydration. And all the while it felt as if his soul was shrieking, pleading with him, with anyone to do something to help his mom.
Dean had gone out, so Sam was all alone. For that he was glad. He didn't want his brother to hear his sobs or see his tears. He didn't want him to know just how much he hurt.
His body finally let him stop crying, though his chest now ached. He clambered to his feet, his legs and arms quivering. Sam dragged himself into bed, and he passed out from emotional and physical exhaustion. His last thoughts as he fell asleep were of hope. Hope that this wasn't real. Hope that Lucifer wasn't really in his head. Hope that his mom would be okay. Hope.