Like many of the stupid things Sam does, it happens too quickly for Dean to stop it. Once minute he's on his ass in the damp slippery grass, fallen like a goddamn amateur, watching the spinthaak advance and hoping he can get off a shot before it rips his head off. The next minute Sam's charging between him and the spinthaak, close enough (too close too close too goddamn close) to shoot it right between the eyes. Dean sees its tail twitch forward before it goes down and he rolls out of the way, because he knows what's at the end of a spinthaak's tail. He hopes to god that Sam got out of the way in time. But a strangled cry of pain puts his heart in his throat.
Sam's on his knees, pawing at his chest, and in a second Dean's in front of him. He tries to pull his brother's trembling hands away to check for blood, because a spinthaak has pretty big fucking claws, too. "Sam. Sam! Did it get you?"
"I'm okay. Kill it." Sam bats his hands away and waves toward the spinthaak's corpse. He clutches his chest again and sinks to the ground with a groan.
"It's dead," Dean says. "You got it. You got too close, you moron! Where did it get you? Did it sting you?"
Of course it did, of course it did, because nothing but a spinthaak's sting would put him in this much pain. Sam's curled up on the ground, writhing, whimpering, and Dean doesn't want to think about what it takes to make his brother fucking whimper.
(But he already knows. He's had John Winchester's voice murmuring in the back of his head all morning. Spinthaak venom. Just a tiny bit in each quill, but it's one of the most painful things a human being can ever experience. Knew a fella got stung in the finger, said he'd have shot his own arm off if his friend hadn't been there to stop him. But the pain isn't what takes you out. The venom is a paralytic. The quill burrows its way to your core if you can't yank it out fast enough, gets to your heart or your diaphragm and boom, you're gone. No antivenin, no CPR. Your only hope is to get that quill out before it's out of reach. And you'll be in too much pain to get it out yourself. That's why you never hunt a spinthaak alone.)
He grabs Sam by the shoulders and rolls him onto his back, pushing his jacket and shirts aside, and gently prods his skin, looking for an entry wound. There it is. Deceptively small, a slightly swollen red pinprick right below his collarbone. Jesus fuck, it's already so close to his heart, and he knows it's getting closer, the deadly quill burrowing deeper beneath the surface. It's got to come out, now.
"Fuck." He runs his hands over his face. "Okay. Okay. I have to cut the stinger out. It's gonna reach your heart if I don't. I've gotta do it here and now."
Sam doesn't answer; he just keeps making wounded animal noises and rocking back and forth. Dean doesn't even know if he can hear him, but he keeps talking, to reassure himself as much as Sam. "No time to get the kit." He digs for his pocketknife and lighter. "We'll do this old school. It'll be fine, okay? You're gonna be fine." He holds the blade in the flame for a minute. It's not enough, he knows it's not even close to enough, but he can worry about infection later. Don't worry if you can't swim; the fall will probably kill you.
"All right. Here we go." He straightens Sam again, presses him flat against the ground. "You gotta hold still, man, okay? Sammy? Can you do that? You gotta hold still for me." Sam nods and then screws his eyes shut and bites off a scream as he's rocked by another spasm of pain. Shit, he's going to bite his tongue in half. Dean yanks off his belt. "Sam. Sam! Open your mouth. Bite on this." He jams the leather between Sam's teeth, takes a deep breath, and begins probing the wound with his knife. "I'm sorry, man. I know this is hot." Sam shudders and gasps, clenching fistfuls of grass, panting as Dean pushes the knife further. "That's it," Dean murmurs. "Keep breathing. You're doing great. You got this."
Sam's legs start thrashing, pushing against the ground. "Please, Sammy, you've got to hold still," Dean sighs. He throws a leg over Sam and straddles his body, resting on his thighs, his feet hooked over Sam's lower legs. Sam's eyes fly open, wide with terror, and he clutches at Dean's arms. "I'm sorry," Dean says. "I have to keep you still. Okay?" Sam nods again and Dean takes his brother's hands and places them on his own knees. "Here. Hold on." Sam's fingers dig into denim as Dean goes back to digging for the quill. "It's okay," he says. "You're gonna be okay." There. There it is. Something solid at the tip of his knife. Sam pushes his head back into the ground and shrieks around the belt, squeezing hard enough to bruise Dean's kneecaps as he works his knife below the quill to guide it back up toward the surface.
Suddenly Sam reaches for the belt and wrenches it out of his mouth. "No gag," he pants. "Please."
Gag? Sam thought he was fucking gagging him? Jesus. Dean keeps prodding at the quill, easing it out. As he leans closer, he can hear Sam whispering something that sounds, maybe, like not back there, not back there and ah, fuck.
"Doing good, Sam," he says, partially to reassure Sam but mostly to drown out what he's whispering because Jesus fuck, Dean cannot think about that, cannot think about what memory Sam might be reliving, back there, held down and gagged and in excruciating pain. "Almost there. So close." Sam covers his face with his hands and lets out a long, drawn-out moan as the end of the poison quill surfaces. "There you are, you fucker," Dean mutters. He has to resist the urge to grab the quill and yank it out of Sam's flesh. Don't squeeze the end, John Winchester's voice barks. That's where the venom is. You'll squirt it right into him.
"Okay, okay." Dean can reach the dark center of the quill now, and he gingerly grasps it. Watch it, son, it's going to be slippery from blood. He eases it out and sits up, trembling with relief. "Shit, Sammy." He holds it up for inspection - an inch long, with a barbed tip and bulb at the end the size of a sesame seed; such a tiny thing to be responsible for so much agony. "Look at that son of a bitch."
But Sam's still keening, still breathing in ragged gasps, still clutching at his chest. "Oh, god, it's still burning, it's burning, Dean, it's still in there."
There's another one. But it's okay. Dean can do this. He stops to scream "fuck!" up into the sky, then takes a deep breath. He can do this. "Okay. Okay. One down, one to go. It's okay. It's gonna be okay." He uses his shirttail to wipe the blood off Sam's chest (Sam's heart hammering against his hand, galloping out of control) and plants his hands on his upper arms (quivering, slick with sweat) to hold him down and keep his hands out of the way. "I'm sorry, Sammy. You gotta try to hold still. I can't find it. Where does it hurt?"
"Everywhere," Sam moans. "Oh god, get it out, get it out, please, Dean." His breath is ragged and shallow; his lip is bloody from where he's bitten it, and his whole body is shaking. Dean struggles to keep him steady with one hand as his fingers run lightly over Sam’s chest, looking for the second entry wound. After a lifetime he finds it, a tiny swelling hidden inside his tattoo and fuck, that's so much closer to his heart and Sam’s whispering not back there, not back there because apparently he has to convince himself he’s not back in Lucifer’s fucking cage and Dean's running out of time and he doesn't think he has the strength left to keep restraining his delirious, struggling little brother.
"Sam," he says sternly. "Sam. Listen to me. He likes it when you squirm, Sam. Don't give it to him. Don't you do that for him. You stay stiff as a board and let him go fuck himself. You got that?"
Sam stares at him in terror again, then takes one long, shuddering breath, closes his eyes, and stills.
"There we go." Sam's still trembling but not kicking, not thrashing, not fighting him. "It's okay, it's okay." Dean inserts the knife and cuts down further, and when he finally reaches the quill he can't think about the bulb of venom, he can't think about grasping the center of the shaft; he's got to get this fucking thing out of his brother right now so he whispers fuck, Sam, I'm sorry and grabs it and and he pulls. Sam cries out, kicks and thrashes, then his eyes roll back in his head and he goes limp.
There's a pinpoint of pain, needle-sharp, tiny but intense, and then another, and then the points of pain expand, spreading fiery, white-hot hurt across his chest. His legs buckle and he crumples to his knees, clutching at his chest, trying to put out the fire but he can't, it's inside, it's under his skin and lapping at his flesh. He wants to call out to Dean but Dean's busy, Dean's finishing the spinthaak, so he tries to bite it back but it comes out as a whining scream, and then Dean is at his side, wide-eyed. "Sam. Sam! Did it get you?"
Sam pushes him away, waves toward the spinthaak, or at least where he thinks the spinthaak must be. "I'm okay," he gasps. (He's not okay.) "Kill it."
"It's dead," Dean says, with a quick confirming glance over his shoulder. "You got it. You got too close, you moron! Where did it get you? Did it sting you?"
Sam's on the ground now, he thinks, but he doesn't feel anything but fire - every nerve in his body is throbbing, tethered to his chest, to the fire charring his ribs. "Oh, god," he moans, as Dean grabs his shoulders and rolls him onto his back.
Dean pushes Sam's jacket and overshirt aside and pulls up his t-shirt. He gently prods at his chest and his fingers are cold, so cold against burning skin. "Fuck. Okay. Okay. I have to cut the stinger out. It's gonna reach your heart if I don't. I've gotta do it here and now."
(Oh yes god please get it out here and now please.)
"No time to get the kit." Dean releases Sam to dig for his pocketknife and lighter, and Sam curls back into himself and god, it hurts so much, it's like flaming spikes are being hammered into his flesh. Dean's still talking, keeping up a continuous patter of reassuring white noise as he runs the blade through the flame of his lighter. "We'll do this old school. It'll be fine, okay? You're gonna be fine."
Dean pushes him flat against the ground. "You gotta hold still, man, okay? Sammy? Can you do that? You gotta hold still for me." It's too much, it's too much like being restrained (tied up strapped down chained) but Sam nods because it's not Lucifer, it's Dean, and Dean will take care of this, except being held down hurts so much and Sam screams again, trying so hard not to scream, bites his tongue, bites his lip.
"Sam. Sam. Open your mouth. Bite on this." Something is shoved into his mouth; it tastes like dirt and blood and fire and brimstone and it's firm but yielding when he bites into it, not slippery, nothing like his own intestines, nothing like his heart or liver or a red-hot iron rod or any number of things that have been shoved into his mouth.
Dean's hands are like ice on his chest; his flame-purified knife is an icicle compared to the fire consuming Sam from the inside. Cold fingers pry inside him, peeling him apart, groping, searching. Sam squeezes his eyes shut and he can't open them, can't can't can't because if he does he's going to see Lucifer rooting around inside of him, pulling him to pieces with long, cold fingers.
His legs start kicking, trying to crawl away from the pain, because Sam's brain knows (thinks) this is Dean but his body is screaming no, no, get away and then something heavy is holding him down and he can't move and oh god it hurts and he's afraid to look but he does and it's Dean, it looks like Dean but that doesn't mean anything, doesn't prove anything.
"I'm sorry," Dean says. "I have to keep you still. It's okay."
It's Dean and it's okay except oh fuck, it's not okay, he's on fire, he's burning up on the inside, his blood is molten lava spreading the fire though his body and someone's cold, cold fingers are poking inside of him and the gag between his teeth tastes like hellfire and ash. He yanks it out of his mouth and says "No gag. Please." Dean doesn't argue and that proves it's Dean, it's not Lucifer, because if Lucifer wanted him gagged, he'd fucking be gagged, so it has to be Dean, even though Sam's burning and the fingers inside him are ice and oh fuck everything hurts. But Sam's not back in Hell, he's not back there, not back there.
The icicle pierces him further and Sam keeps trying not to scream and trying not to push Dean away because Dean's saving him, Dean's cold hands and icy blade are going to put out the fire, and Sam reminds himself that he's not in Hell, he's not in Hell. Then the frozen fingers are gone and Dean crows triumphantly but it can't be, it's not gone, Sam can still feel the fire spreading through his body. His hands are free now, and he reaches up to his chest and tries to claw the pain out. "Oh, god, it's still burning, it's burning, Dean, it's still in there."
Dean screams "fuck," icy palms planted on Sam's chest. "Okay. Okay. One down, one to go. It's okay. It's gonna be okay." He swipes at Sam's skin with his shirt, wiping away blood, icy fingers prodding, poking, in search of an entry wound, asking where it hurts, but it hurts everywhere, from the tips of his hair to his toenails, his whole body is in agony. He tries to crawl away from the pain again but someone (something) traps him, holds him down, demands his attention.
"Sam. Sam. Listen to me. He likes it when you squirm, Sam. Don't give it to him. Don't you do that for him. You stay stiff as a board and let him go fuck himself. You got that?"
He opens his eyes and he can see him now, Dean or something like Dean, towering over him, blocking the sun. If it's Dean (it has to be Dean oh please God) he needs to do what he says. If it's Lucifer it doesn't matter. Sam takes a breath and his fingers dig into the earth at his sides and he locks it all down, no kicking, no fighting, because someone has set him on fire and someone is dissecting him with ice and someone keeps telling him it's okay, it's okay and someone wants him motionless and maybe they're all Dean, he doesn't know any more but he's not back there, he's not back there, if he keeps saying it then it will be true, and then Dean says I'm sorry and there's a white hot explosion in his chest and he kicks out and screams and he's sorry and everything goes dark.
When he comes back, it's to a more familiar set of pain. Rough ground and small stones underneath him, the dull ache of muscles that had been clenched in agony, the sting of a bitten lip, the sharper sting of alcohol on a wound, the low throb of a jaw long clenched in pain, and the sudden stab of a needle, of Dean stitching up his wounds.
"Hey." His voice is dry and ragged, and he's shaken by a spasm of coughing before he can say anything else.
Dean startles at the word, and quickly sits him up with a hand supporting his back, pushing a bottle of lukewarm water to his lips. "Shhh. Don't talk. Drink." Sam’s mouth tastes like blood and dirt, and he spits out a mouthful before draining the rest of the bottle.
"All right,” Dean murmurs, easing him back onto the ground. “Let me finish up here. You okay?"
"Fan-fucking-tastic." A stab of the needle again, as if for emphasis.
"You didn't get hurt?"
"Only my pride. Can't believe I let that thing knock me on my ass. And I can't believe you jumped in front of it, you dumb shit."
"Someone's gotta save your candy ass."
“Yeah, well. Don’t let it happen again.” Dean continues stitching in silence, head down in concentration. When he speaks again, he doesn’t look up.
“Look. I’m sorry.”
“For what?” asks Sam, confused.
Dean looks up now, eyes narrowed. “How much of that do you remember?”
(He remembers everything.)
“I remember I was in a lot of pain. I remember you doing whatever you needed to do to save me. I don’t remember you doing anything you need to apologize for.”
“Okay.” Dean nods solemnly at the ground. “Okay.” He stands up and offers Sam a hand. “Come on. Let’s go burn this fucker.”
Sam takes his hand, climbs slow and stiff to his feet, and begins the process of forgetting that his brother knows what appeals to the torturer.