The whole world seems to slow down around Derek as he runs. He threads his fingers together, one palm on top of the other, and presses them over Peter's cold hand. His skin is slippery with blood, but the flow is still streaming steadily, so he could still be alive. He could still be alive, Derek just has to—

Peter lets out a wretched gasp, grabs a fistful of Derek's shirt, and pulls Derek's face nearer to his.

"Wolfsbane… bullet," he manages.

Derek's stomach twists. So Stiles' father wasn't just posturing.

"What do I do?" Derek asks.

"Find… another," Peter says. He's so pale he's practically translucent, veins ink-blue through his skin. "Before—" Peter says, but he shakes his head and lets Derek go.

"Another bullet?" Derek asks. He can't imagine why that would help, unless Peter just doesn't want to die alone.

"And… a lighter," Peter says, before turning slightly sideways and hacking up a new river of black blood. Derek's only seen black blood once before, and it's a dizzyingly inconvenient distraction, but somehow he gets back to his feet.

Alan Deaton has wolfsbane bullets. That's where Stiles' father said he got them. It's a better gamble than trying to track down the gun Stiles' father is probably still carrying, or searching the Stilinski house for any spare ammo he might have left behind. Derek's wolf would probably take the opportunity to curl up in Stiles' bed and never move again.

At least Scott doesn't have work today, so all Derek has to worry about is Deaton. And finding the right bullet, and getting back in time to—to do whatever the cure is before Peter dies again. It's becoming more and more obvious how hopeless Derek would be without him. He doesn't even know how to cure a wolfsbane bullet, if that's even what Peter's plan is supposed to do. Derek's stomach is clenching, already, at what the lighter might be for.

But he doesn't have time to panic. He crashes through the door of the clinic, skidding to a stop inches from Deaton, who says calmly, "The door was open, Derek."

Derek definitely doesn't have time for Deaton's Peter-brand habit of taking forever to say nothing you actually need to know, while refusing to leave out anything else. He goes for the direct approach.

"I need a wolfsbane bullet," he says. "The same kind you gave the sheriff."

Deaton seems unfazed by the request.

"Maybe you didn't hear me," Derek says, low. "I need that bullet. And you're gonna give it to me." We can do this the easy way or the hard way is almost definitely too hackneyed to be taken seriously, but Derek's running out of time.

"You can help me," Derek says, as threateningly as he can manage, "or you can watch me tear your throat out." His wolf stirs in his chest. Derek allows his mouth a corner of a grin. "With my teeth," he adds. It's a pretty good threat, considering Derek isn't an expert or anything. It sounds like something a bad guy would say in a movie before everyone did whatever he wanted.

Deaton just smiles serenely.

Derek glares back. He can't help but feel like Deaton is laughing at him, and it's hard being intimidating when the human who's supposed to be scared of you is practically mussing your hair and calling you Der-bear or something. Derek grits his teeth, stops wasting time talking. His fangs grow in his mouth, his claws inch out over his nails, and he leaps.

He's just going to shake Deaton up. He isn't actually going to hurt him. But he can't help hearing Mr. Tate's voice in his head, and it slows him just before his claws hit a nerve-jarring wall of nothing.

"Mountain ash," Deaton says from behind the barrier. "Now, if you'd like to explain, maybe I can help you."

"The sheriff shot Peter," Derek bites out resentfully, "with the bullet you gave him. I need another so the last relative I can actually find without a map and guide or a really good psychic doesn't die. Again."

"Ah," Deaton says. "So your uncle isn't hurting you?"

Derek glowers. "I'm about to hurt you if you don't—"

Deaton shrugs amiably.

"Just—" Derek says tightly. He exhales hard through his nose. "What do you need me to say?"

"What is your uncle planning?" Deaton asks.

"Human sacrifice," Derek says flatly.

Deaton watches him for a few moments before he smiles slightly, nods. "Let me find that bullet for you."

"And a lighter," Derek says.

Peter somehow manages to look even worse when Derek gets back. His eyes are open, which only means he looks like he died with his eyes half-lidded, which is exactly what Derek would expect of him.

"I got it," he says, heart clanging loudly in his ears. Peter's eyes flicker. "What do you need me to do?"

"Open the bullet," Peter says. His voice has a horrible wet rattle in it. "Carefully."

"And?" Derek says, when he's done this.

"You see the wolfsbane inside?" Peter asks.

Derek more than sees it. His nose itches. "Yes."

"Set it on fire," Peter says, before his voice devolves into hacking and black blood fountains from his mouth again.

"What?" Derek says, barely keeping his hands from shaking and scattering poison all over him.

"Set it on fire," Peter says hoarsely, wiping his mouth. His eyes are watering. It's the closest he's ever looked to a real person.

"The—the bullet?" Derek says weakly. It'll explode, won't it? The fumes will probably kill both of them. Maybe Peter just wants Derek to kill both of them.

Peter sighs, spits blood into the black pool around him. "I need—the ashes," he manages.

Derek's hand shakes around the lighter. The smell is unbearable even before his faltering fingers get a flame. Derek can see his pack, hear them, feel the blistering heat around them. His eyes sting, vision a blur.

"Give it to me," Peter says, holding out a surprisingly steady palm. Derek's hands are trembling so bad he practically sets himself on fire. He can barely see three feet in front of him through the tears, but somehow he hands it over, and Peter does what Derek couldn't. He presses the smoking stuff against the wound under his palm and closes his eyes.

"Some people will do anything for their pack," Peter says. Derek's slumped on the blood-sticky stairs, watching him continue and continue and continue to be alive. That cure or whatever it was didn't make any sense, but the wound is already gone, leaving no trace but the blood all around them and the faint but still horrifying scent of smoke hanging in the air.

"I'm sorry," Derek says, his throat constricting and constricting and constricting. His eyes go hot, spill over again.

"Some alphas tie their betas' pain to themselves so they can tell when their pack is hurt," Peter goes on, like Derek hasn't said a word. "Others simply tie their family's life force together. Think of a cup, filled to the brim with the strength of the pack. If the alpha dies, instead of their share of life force returning to the world at large, it stays in the family's cup, so that their absence doesn't leave their pack vulnerable."

He pauses, probably for effect, before adding, "Your mother did both."

Derek's throat is impossibly hot and tight, but he nods, accepts this, before his mind floods with what must have happened to Mom during that fire. He barely keeps the sudden sickness down.

"But this arrangement didn't die with my sister," Peter says. "In fact, it's probably the only real reason any Hale is still alive."

Derek swipes at his eyes, stares at Peter.

"My abuse two nights ago should have killed you," Peter says. "But I knew it wouldn't. Just as I knew that bullet wouldn't kill me."

Derek can't help the outrage that pours through him then. He'd really thought—he'd been half sure, ever since finding Peter in the doorway, that it was already over. That he was gonna be the only one left, again.

"Yet as invaluable as your mother's power has undoubtedly been through the years, it can only stream in one direction," Peter says. "Had only Talia survived, the bond wouldn't have helped her, because she'd never dream of taking power from her betas."

Of course Mom wouldn't. Derek feels a sudden wave of longing so heavy it nearly drowns him.

"It was your father's death that inspired my sister to do this," Peter goes on. "The thought of finding another member of her pack like that terrified her. The bond was a way for her to honor his memory at that most difficult time, while quelling the fear that something like that could happen again.

"And without it," Peter adds, after a few moments' silence, "I couldn't have come back."

Derek can barely hear him, buried under nostalgia so thick he could choke on it. He can feel Mom, suddenly, all around him, and it's almost impossible to notice anything else when all he wants to do is curl smaller, smaller, smaller, until he's engulfed completely.

"To bring our family back without the benefit of mass sacrifice, the bond must go full circle," Peter says, his voice growing stronger as Mom slips away. "I don't want to kill to bring my sister back. But I need your help with the alternative."

Anything, anything. Derek almost wants to change his decision, bring Mom back first, but the thought of having Dad here to welcome her is too strong. It would fix everything, make up for everything if Derek could do that.

Heart in his throat, already impatient with the lack of them, Derek says, "Tell me what to do."

Derek almost expects to dream of family, of his parents, Dad's death and the fire and their resurrection, but instead he dreams of Kate. Kate all over Stiles, kissing Stiles, claiming him. Taking and taking and taking, and Stiles thinks she's Malia, so he's letting her. Letting her touch him, letting her make him hers, and Derek's trying to warn him but he cant speak, and Kate looks at Derek struggling and laughs and laughs and laughs—

And suddenly Derek is at Stiles' side, in Stiles' room, taking him back desperately, breathing him in, and there isn't a trace of Kate anywhere on him. There's just Derek, and under, Stiles' father, a little bit of Scott—

But Derek kisses him hard, smiles sharply when he pulls back and Stiles is wide-eyed and breathless, pulling Derek in close again.

"Wait," Stiles says, and everything stops at once. A thousand Kates laugh in the sudden silence. You you you you you you think I wanted to touch him?

Stiles' hand finds Derek's wrist. "You went back to him," he says quietly. "Last night. Did he—do something?"

Derek shakes his head impatiently.

"Did he threaten you?" Stiles asks, softer. "Or—us?"

Us.

It's a cold hard stone in the gut, the Us that is Stiles in Scott's pack. Derek shakes his head again.

"Because if he did—"

"He didn't," Derek snaps. "Not even after your father shot him."

Except he couldn't have said that, because this is a dream. You can't speak in dreams. You keep trying, but the words get stuck in your throat.

"That's nightmares," Stiles says, his eyes very bright. "And he hurt you again, I couldn't just—" He stops, says desperately, "He almost killed you, and then you came back hurt again, and you wouldn't say a word. I thought he did something so you couldn't talk."

"He didn't hurt me again," Derek says. It sounds weak, a ridiculous defense, but it's true. "And he didn't attack me, it was a fight. I started it. I lost." It's so obvious. Peter knew he'd be okay, he was just trying to stop Derek hitting him. Maybe the alpha power went to his head a little, but he knew Derek would be fine. Why can't anyone else understand that? "You're just looking for an excuse to—to put us down."

Stiles goes very still. "Is that what he's telling you?"

"He doesn't need to tell me," Derek says.

"Right," Stiles says. "Because it's so fucking obvious, right? Because I'm obviously seconds away from, from—" He shakes his head. "Hit me."

"What?" Derek says, stepping back cautiously.

"Hit me," Stiles says. "Attack me. Start a fucking fight. Whatever you did to him."

Derek doesn't move.

"Come on!" Stiles snaps impatiently. "You hate me, right? Because Scott didn't tell you his master plan, which he didn't tell me either by the way, and I didn't drag him off you because I was freakin' paralyzed, I didn't even think, and because I didn't know you weren't a serial killer until Peter put his claws through your spine, I mean I knew, like a gut feeling, but I didn't actually know, it was just an instinct, and older you looks like someone you don't want to meet in a dark alley, and you could have just told Scott you didn't bite him instead of assuming he'd see it like the privilege it obviously was for you and, and taking credit through vague bullshit non-answers, but whatever—and oh yeah, I harbored your wanted ass while Danny tracked Peter down to the hospital, where you realized surprise, the alpha that's been murdering people, that literally left you for dead, looking permanently dead by the way, is your very own sweet supposed to be comatose uncle." Stiles takes a deep breath, keeps going. "But I'm the worst, right? And Peter's obviously not up to anything that's gonna blow up in all of our faces, he's got a heart of gold-plated marshmallow, he's just really misunderstood."

Derek can't listen to this, can't take in a word Stiles is saying. It's just a dream, just a stupid dream trying to confuse him. His wolf, or his new paranoia, or—He's gonna bring his family back. He's gonna bring his family back, and none of this matters.

"But you know what?" Stiles goes on, like he's been preparing for this all day and isn't gonna run out of material for hours. "You did turn kids without warning them, and you did turn Erica in a freaking hospital room after she'd just had a seizure, and you did caress her thigh or something that made her think you wanted to fuck her, and you know what? That was fucked up, and Scott was right to worry about it. But you know what else? You didn't kill her. You did your best to protect her, and all your betas. When, when Cora and Boyd were feral, you let them tear you to shreds so they wouldn't kill each other. You didn't know what you were doing half the time but you tried your fucking best and you did everything you could to stand in the way of anything trying to hurt them. You could've become a really good alpha," Stiles says, finally losing steam, "and the only reason you didn't get the chance is the alpha pack, okay?" His voice goes soft, sorry. "Go ask Peter who threw Boyd onto your claws. Or who held you in place until it was over. Or who kidnapped Erica and Boyd and Cora and locked them in a bank vault for months. And ask him who kept searching for them every day for months, who wouldn't give up on them—" Stiles stops. "But Peter wouldn't know the answer to that," he says, so quietly. "Not like I do. Because he wasn't there, looking with you, all summer."

It all sounds so horribly true, but it can't be. Not when Derek's so close to getting his father back. Peter's plan makes sense. It doesn't matter if he lied if he brings back Derek's family.

"I know you, Derek," Stiles says, stepping forward slowly. "Maybe you don't know me anymore, but I know you. And you—you hate fighting. Even when you don't have a choice. You'd never hurt anyone, not really. Not enough that they'd need to defend themselves. Even when you killed Peter, he had to convince you to do it, and you still closed your eyes." His hands slide up Derek's spine, find their perfect placement. Derek struggles not go limp underneath them. "There's no way what he did to you was self-defense, Derek," Stiles says, eyes pleading. "You have to know that."

Derek kisses Stiles quiet again, tries to shake off the feeling that he got it all wrong all over again. Stiles kisses back deep and certain, but after, he opens his eyes, says against Derek's skin, "You can't go back to him."

Derek jerks back. Means to jerk back. Ends up rooted in place, still breathing Stiles in, even as he says harshly, "I can do what I want."

But it doesn't come out harsh at all. It comes out like a plea, like he needs Stiles' permission.

"Right," Stiles says.

"Peter's gonna bring my father back," Derek tells him. He doesn't mean to. He just can't stand the closed-off look in Stiles' eyes, the momentary flash of betrayal before it.

"Sure he is," Stiles says. "He's a real bleeding heart that way."

"Stiles," Derek says. The way Stiles is looking, sounding, cold and distant and—It's unbearable. "I'm just trying to fix it."

"And you really think—"

"I'm doing this," Derek says. "I have to do this. I can't live like this, Stiles, I can't—"

"Sure," Stiles says. "Trust the guy who legitimately keeps trying to kill you, and accuse me—" He takes two sharp breaths, lets them out shakily. "I can't just keep waiting for you to show up like this," he says. "I'm—I'm spending the whole day expecting to stumble onto your body, I'm texting Lydia every five minutes in case she's getting a feeling, and then at night you just—show up, like nothing—" He shakes his head slightly. "I'm gonna lose my mind. Again."

"This is a dream," Derek says uncertainly. "The real you—"

"Just go," Stiles says, pushing him through the doorway. Derek can see him even as the door slams, sliding down it with a sob, burying his head in his hands. His heartbeat crashes like the tide, makes Derek sink against the door too, struggling to remember through the heartsick fog that none of this is actually happening. None of this is real. Any minute now he'll be back on Peter's porch, blinking up at too-bright sunlight, back in the solid, dependable day, where none of this actually matters, because the real Stiles doesn't care about Derek at all.

The softest little shudders filter through the door, settle in Derek like millstones, work a terrifying sick hollow all through him. Dread creeps cold under his spine, swallows him whole. Derek waits, and waits, and waits.

The world stays horribly still and sharp and solid. Stiles' misery tugs at Derek, drags the air out of him.

His wolf whimpers.

He keeps waiting.

He doesn't wake up.