Dean was losing himself. He wouldn't be himself much longer, not ever.
Sam was the cure.
'The river flows back to the source.'
If Dean... killed him... the mark would be gone.
"Don't you come in, Sam. Don't you dare come in."
Sam could pick up Dean's shaking voice from somewhere behind his door, the sincere note of pleading in it twisting the younger brother's insides. Fear. In that moment, Sam knew fear in a way he never had before— its overwhelming presence beginning to crush him. And although he genuinely made an effort to keep the growing trepidation out of his tone, the quiver in it betrayed him.
"Dean, whatever you're doing, stop. J-ust stop." One hand was spread over the wooden surface of the door while the other was already wrapped around the handle. A slight turn on the golden knob without resistance confirmed it wasn't locked, but the second Sam applied pressure, Dean protested vehemently.
"Don't! You can't… if you come in you won't come out, you hear me!?"
The undeniable brokenness in the words felt like a knife digging in his flesh.
"It's too strong… I won't be able to fight it, I won't. You can't come in here… you have to let me do this. I'm going to put a stop to it."
Even before Dean finished the sentence, Sam was shaking his head in refusal. No. He knew exactly what Dean meant, he knew precisely what weapon his brother had in his hands. And no. It couldn't be like this, it couldn't end like this. Not like this. The mere thought of having to go through all of it again, losing him again… no.
Sam knew he wasn't strong enough. Not again, and sure as hell not like this.
"You can fight it. Dean. You can fight it." Sam responded through the wood barring him from his brother, releasing a shaky breath as he eased his fingers from the handle, wanting to avoid any sudden movement that might cause Dean to do something stupid.
"We'll figure it out. Remember? That's what you said, that we'll figure it out… like we always do." He felt so young suddenly, so helpless, being thrown face to face with the loss he'd dreaded with his entire being. There was nowhere to hide and nowhere to run.
Just like when Sam had watched Dean struggle with death in a hospital bed when he was in a coma. Or when he bled out in that parking lot after being shot because Sam hadn't been paying attention not long afterward. Or when Dean had sold his soul for him, when the year had run out, and he was gutted by hellhounds right in front of him. Or maybe when Metatron stuck him with an angel blade.
The common thread in all the situations? Sam was powerless to stop anything. No matter what he did, regardless of what he promised, he could never save Dean.
It was an insecure helplessness laced with guilt Sam hadn't fallen under in a long time, so when it hit—it hit hard, and Sam was scared. Scared that this time would come out like the others.
"Don't open the door," Dean's voice was quieter than before, "… Sammy… please. If you've ever given a damn about me. Walk away."
Sam shut his eyes, as if doing so would help ease the tension. Or the pain. Or the ever growing fear, gnawing at his brain. And maybe this made him selfish, well… yes. It did make him selfish. Hell, it probably made him despicable, because he knew what Dean would suffer if he went through with the cure. Sam knew the guilt would prove too much for him, how even if he understood the circumstances were well out of his control, he'd damn himself to hell with blame and self-loathing if he could. Sam knew.
And still… everything in him, every fiber of his being weighed with the compulsion to open the door, walk in, and fix what was broken by satisfying the mark once and for all. Dean would be free… saved. And wouldn't that be worth it? Dean had moved on before… maybe he could do it again.
"Dean…I can't."
"I swear to god, Sammy, if you—"
Sam steeled himself, ignoring his brother's words.
He opened the door.
Dean was crouched in the furthest corner from the door, fingers wrapped around the first blade and shaking. Sweat beaded along his forehead, and the hazel eyes Sam knew so well were full of that uneasy darkness Sam had learned to recognize as the mark's sway. But they were also full of something else; fear. The same fear mirrored in the younger brother's emerald hues.
"Damn.. you son of a bitch." Dean's voice nearly cracked, heavy laden with a familiar hatred spiced with betrayal as he turned his head away from Sam, a tear slipping from glassy hazel eyes. "I'm not deaf, Sam, I know what the cure is. And you can't make me do it. You can't… Sammy, not that."
a/n I know this is short, I apologize- Depending on the response, I mean, if it's wanted haha, the next chapter I'll definitely make longer. Thanks for reading!