When he gets back, Stiles is sitting in the dark, waiting for him, his face lit by the glow of his phone.

"Where were you?" Stiles demands, standing up sharply. The shadows under his eyes are worse than ever, and there's something wrong with his heartbeat. "I thought—You can't just disappear, okay, I—"

"I went for a run," Derek says.

"To where, New York?" Stiles' hair is a mess; Derek has a weirdly vivid mental picture of him dragging his fingers through it. "It's been six hours, did you go to running school?"

"I can go where I want," Derek says, bristling. He hates this, Stiles treating him like—like some little kid who has to be looked after. Checked up on.

"Yeah, and you can also, I don't know, tell people where you're going, so they don't just lose their—" Stiles rubs his eyes, drags his hand down his jaw. "We just paid fifty grand to get you back, I think you owe us a little—"

So that's all it is.

"I don't owe you anything," Derek says. The words come out sharp, angry. "I don't even know you."

"You're right," Stiles says. "You don't know me." The look on his face—Derek backs up, nearly hits the wall.

Stiles' hand shoots out to cushion the spot just behind his head.

"Hey," he says lightly. "I'm Stiles." He leans closer, tells Derek's ear, "I'm the guy who keeps saving your reckless werewolf ass."

He licks his lip, watches Derek squirm, but Derek can hear his heart, pounding out of control even worse than when they found him.

"You want a list?" Stiles says. "Because I can make you a list. I can make you a list of lists. There is no end to the sheer amount of—" He catches Derek's eye, cuts off, starts counting on the fingers of his free hand. "Okay, so, the wolfsbane bullet, the, the kanima by the pool, Jennifer, this is twice now you've been kidnapped by the same nut by the way, maybe the fifth time Scott and I had to track you down and find you like—" He huffs out a sharp breath, adds, "And, oh yeah, we just drove to Mexico to get you back. Scott and Lydia just got kidnapped, Scott was tortured looking for you, you could maybe at least—"

"I never asked for your help," Derek says coolly, but his throat is on fire. He's not some—some little brother Stiles has to keep track of, he's not even in Scott's pack. Stiles should just leave him for dead if he's that much trouble.

"You don't need to ask," Stiles snaps.

"Scott's not my alpha," Derek says, "I'm not even in your pack. So why don't you just leave me alone?" Derek can take care of himself. He's going to look after Kate, protect her, he's not some useless kid, some dead weight Stiles has to drag around, stay up worrying about.

"Why—" Stiles mouth opens and shuts a few times before he says, eyes narrowed, "I thought we were friends, jerkoff, I'm just trying to—"

"Yeah?" Derek challenges, his own heartbeat thundering in his ears. "Because right now? You seem more like my stalker."

Stiles goes still, backs away. The back of Derek's head hits the wall with a thud.

"Fine," Stiles says. "Don't tell me anything. It's not like—" He scoffs. "Whatever."

"Not like what," Derek says, some kind of fire still burning in him, almost drowning out the sick feeling of the split second of shock on Stiles' face, the way it went blank so easily. "What, were we some kind of—"

"You know what?" Stiles says, throwing his hands up and stepping back again. "You can do what you want. It's your fucking life."

"Yeah, it is," Derek says.

"Well, great," Stiles says. "Guess I'll see you around then. Or, you know, not."

He walks away, leaving Derek still pressed against the wall, heartbeat drumming manically in his ears.

For the rest of the night, Derek lies in Stiles' bed, staring at nothing.

He doesn't dream.

Stiles' father intercepts him on his way out. "Going somewhere?"

"Home," Derek says. This is stupid. He has his own apartment, he doesn't need—

It's just stupid.

"I don't think that's a good idea," Stiles' father says.

"Why not?"

Stiles' father sighs. "You've been through a tremendous loss, Derek, it's natural to want to close yourself off to people—"

"I'm not," Derek says. "I'm going home. To my girlfriend."

Stiles' father raises his eyebrows. "Your girlfriend," he repeats.

"Yeah," Derek says, irritated. "Thanks for—the food, and everything, but she's waiting, so—"

"Derek, I'm not sure—"

"Yeah, well, it's my life," Derek says. His eyes prickle, burn, his breath catching in his throat, and he just has to run.

He feels the heat of Stiles' dad's gaze on his back for miles.

Kate's ordered food to the apartment: sushi and matcha ice cream, two sets of chopsticks and two plastic spoons. Derek's heart swells. They eat it all on his giant bed, and Derek hardly feels sick at all.

"You should stay here," Derek says, after, shoving the trash bag off the side and lacing his arm around her. She shivers a little, sinks into it. "Until we know you're safe."

"I'll never be safe here," Kate says. For a second Derek thinks she means the apartment, and his heart stutters, but then she says, "Beacon Hills wants me gone."

"Then we'll go," Derek decides, lying back on the mound of pillows. "Wherever you want."

"I'm broke, Derek," Kate says, slightly muffled, her head against his chest, blonde waves spilling over his shoulder. "And I'm sick of running."

"You shouldn't have to." Derek thinks of Peter again, of what he did to her. He has the worst suspicion it's all about him, somehow, like Peter can't ever stand to see him happy. Like this is Derek's fault, really, because everyone around him gets hurt, and he should know that by now.

"You said there's a list," he says, his pulse picking up with a sudden, terrifying idea. "Someone's offering money in exchange for—And you deserve it. And he—"

Kate curls closer, looks up at him through her eyelashes. "What are you saying?"

"Peter's on the list," Derek says.

"I'm sorry," he tells Stiles later. "I—It's been a lot."

"Don't worry about it," Stiles says. He's researching, staring at his laptop screen, doesn't even turn around.

"I don't think you're a stalker."

"Wouldn't care if you did, dude," Stiles says, so casually Derek might've believed him if not for the slightest uptick in his heartbeat.

"Still," Derek says.

"Cool," Stiles says.

Derek just stands there, hovers like an idiot in one of older Derek's oversized shirts, hands shoved in the pockets of Dad's jacket.

"I brought your shirt back," he says.

"Keep it," Stiles says shortly.

"I don't need it," Derek says.

"Then throw it out."

Derek swallows hard, stares down at nothing.

"Any new theories?" he asks, after a while.

"None that hold up," Stiles says.

The silence is a sound; Derek can't stand it.

"Malia's your girlfriend, right?" he says, eventually.

"Yup."

"And you're her anchor."

"I guess."

"Do you love her?"

Stiles huffs, looks up. "When did you become the talky one?"

"It's just a question," Derek says.

"Yeah, and kind of absolutely none of your business."

"Fine," Derek says.

"It's new," Stiles says, after a few minutes of silent key-tapping. "I'm trying this weird new thing where I don't get totally obsessed with people I barely know."

"How do you know her?" Derek asks casually.

"Wow, you're just full of questions today."

"It's just," Derek says, shrugging a little. "I don't even know my own life."

"Jeez," Stiles says, shutting the laptop with a pained expression. "You're right, I'm the worst. What do you wanna know?"

Malia wants to go to some club, so they go to some club, and Derek watches her grind on Kira and then hang off Stiles' shoulder like he's furniture, drinking a giant bright drink so sharp with sugar it makes Derek's nose itch.

"Hey," Scott says. Derek spins. He didn't hear him coming over the thumping bass. Or maybe being an alpha means you can move without making any noise at all. Mom—

Derek swallows hard.

"Hey," Scott says again, softer. Somehow, despite the music, Derek hears him. "Are you okay?"

It's easily the stupidest question an alpha has ever asked him, but it sounds different from Scott. Genuine.

"Not really," Derek says.

"If Stiles' place isn't working out," Scott says, "my house has a guest bedroom no one's using."

Derek looks at him. "It's not—I have an apartment."

"You should be around people," Scott says, and before Derek can protest, goes on, "Look, I—I'm not your alpha. I know that. But that doesn't mean you're alone."

"Why?" Derek asks. He doesn't mean to, but it makes no sense. "How do we know each other?"

"Peter was my alpha, once," Scott says. "It kind of made us... brothers."

Peter.

"After he—" Derek can hardly breathe. "I was his beta? After he killed—"

"You didn't know," Scott says.

Of course. Of course Derek didn't know, he never does. Not until it's too late.

He feels sick.

"We didn't always get along," Scott says. "But things are different now. They've been different for a while. So if you need—"

"Why?"

"What?"

"Why are things different now?"

"I..." Scott considers this seriously. "I think we just grew up."

Lydia spends forty-five minutes grilling Derek on werewolf lore before Stiles asks her to dance. He winks at Derek over her shoulder before breaking into some of the most ridiculous moves Derek has ever seen.

Derek bites back a grin.

When he looks away, Malia is staring at him.

"Peter," Derek says on the drive home. He's in the back seat this time, Scott at his side. Malia's lounging in the front, her head in Stiles' lap, which doesn't seem very safe. "What kind of alpha was he?"

Scott grimaces.

Derek's stomach tightens.

"Not the kind that gives you a choice," Scott says.

Derek thinks of Paige waiting in that hallway, thinks of waiting like an idiot, stupidly far, for some Alpha to—talk to her, explain—

Thinks of her scream...

"Hasn't changed much, then," Derek says.

"Yeah, no," Stiles says, watching Derek in the rear view mirror. "He was never really the cuddly, heart of gold type. More the... kidnappy, murdery, claw his own beta through the chest and just leave him to bleed out type."

Derek's breath sticks in his throat. "He just left Scott like that?"

"Me?" Scott asks. "No, he didn't do that to me."

"Yeah, he was a little busy trying to compel Scott to kill us to bother with the family package," Stiles says.

"To kill—"

"Apparently you can't be in two packs at once," Stiles says. "So naturally the only reasonable solution is to kill all your friends. And their dads, because hey, once we're getting started—"

His oh-so-casual voice goes brittle over dads.

Derek is so furious, he can hardly breathe.

Except that's not true at all. He's breathing easier than he has in days, anger settling low inside him, turning the weight of everything into focus, into fuel. His wolf, practically playing dead since Mexico, rears its head and roars, and he holds it in place, controls it without even thinking.

He could fight an army on this rage. He could win.

"Where is he?" Derek asks. His voice is very level, betraying nothing. His new anchor rolls smooth and powerful in his chest, gives his slumped spine a new shape. "I think it's time for a family reunion."