The last thing Stiles expects to see when he gets home from school is his cousin Cordelia. Okay, maybe that's not the very last thing, but it's certainly in his top ten list of last things.
He steps inside and she's half standing up and she says, "Oh," with wide eyes and a soft voice. "I wasn't expecting that."
"Expecting what?" Stiles says, right before he feels a sting in his chest, a bit like a fishhook, line taut between him and -- him and his cousin. "Are you magic?" he asks.
"You could say that," Cordelia replies. "Are you?"
Stiles shrugs one shoulder. "Sort of," he says. "A spark. Emissary-in-training."
Cordelia's eyes narrow. "Not anymore," she says. Stiles is rearing up to argue because fuck that, he's seen his cousin maybe five times in his life and he fought for the right to train, no one's gonna walk in here and stop him when even the combined force of Scott's puppy-dog eyes, Derek's glare, and Deaton's inscrutable all-knowingness couldn't. Except then Cordelia says, "We need to talk. Will you hear what I have to say?" and she looks so honestly defeated even with the steel in her tone that Stiles closes the door behind him and makes his way to the table.
"Lay it on me," he tells her, "but this better be good. Oh, but how's Aunt Fiona?"
Cordelia's smile is wry, sadly amused. "Dead," she says. "I promise, Stiles -- you'll want to hear why."
Stiles frowns, but nods. "Okay," he says.
Cordelia isn't his cousin, just like Aunt Fiona isn't his aunt. They're distant relatives of his mom's, share a great great great great great great grandparent in common or someone like that, and mom never liked Aunt Fiona, but family's family and they both came to the funeral, wore black dresses and carried black parasols and set mom's favorite flowers on the casket. Cordelia gave Stiles a fantastically soft yet all-encompassing hug and Aunt Fiona told Stiles he wasn't too bad even if he was a boy and they left packets of sweet smelling herbs that covered up the stench of Dad's whiskey binges.
Stiles appreciated that.
Cordelia writes to him every summer, the letter arriving near the end of June, nothing more than platitudes, really, hopes that his school year has gone well and the upcoming one will as well, a few stories from around New Orleans, the reminder to get in touch if he needs to talk about anything, no matter how big or small or weird.
He always wondered if she was lonely or bored, writing to a kid with such regularity, but now he thinks maybe there's more to it, with her sitting there, watching him, studying him, as if she's able to see inside of him.
"There are seven feats of wonder," Cordelia says, into the silence. "Telekinesis; pyrokinesis; divination; concilium -- our name for mind control; transmutation, which is what we call teleportation; descensum, the gift of travelling to the underworld; and vitalum vitalis, the transfer of life potential. There are other, smaller acts -- clairvoyance, injury transference, resurgence, negation -- but a witch will always present with at least one of the seven wonders." Cordelia leans across the table, holds out one hand, palm up. "How many have you manifested, Stiles?"
"I -- enough that I count," he says. He stares at Cordelia's hand but doesn't move his own towards it. "But I'm not a witch. I'm a spark. An emissary. There's overlap, sure, but I'm not --"
"You're family," Cordelia says. "It's rare but you're one of us. And we can train you far better than anyone else."
Stiles bites his bottom lip. "I can't leave," he says, unable to meet his cousin's eyes. "I have an alpha. A pack. I'm training under a mentor a couple towns over; we're not -- I'm -- my dad, Cordelia."
"We'll make it work," Cordelia says. It sounds like a promise. "There are others who can come here and keep an eye on your father, your friends, your pack. We won't let any harm come to them. Stiles," she says, and this time there's something in her voice, something that tugs at that line between them, that wants to yank his head up to meet Cordelia's gaze. He fights it, resists the urge, and she says his name, his real name, more magic in the word, more power, more demand. "Mieczysław."
"I only submit to my alpha," Stiles says, has to force the words out. "And you aren't him." His eyes are fixed on the wood grain of the table, his mind is screaming out Derek's name, is sending panic and dizziness through the pack bond, and he can feel his cousin's strength of will surround him, coat him with a layer of -- of something that feels confining, tightening, binding. Stiles hates it, refuses to let it win, and he stumbles out of his chair, nearly falling to his knees on the floor when Cordelia grips harder.
A roar, then, outside, and footsteps landing hard on his bedroom floor, a growl that echoes down the stairs a moment before Derek careens into the kitchen, eyes red and fangs extended. Stiles reaches out a hand to Derek, who takes it, stands in front of Stiles, asks, "Kill her?"
"Not if she stops," Stiles gasps out, eyes screwed shut to focus on fighting Cordelia's magic now that Derek's here to take care of the physical battle -- if it comes to that.
"You said spark, Stiles," Cordelia murmurs. "Emissary. You said nothing about mate."
The pain is gone, then, so instantaneously that Stiles lists to one side, nearly faceplants on the floor before Derek stops him, pulls him up and holds him. Everything inside of Stiles aches though Derek starts draining the pain a moment later; Stiles lets out a hum of relief, buries his face in Derek's neck.
"Who are you?" Derek asks. "Why come after Stiles?"
"I'm his cousin," Cordelia says, "and the leader of the coven he rightfully belongs to."
Derek snarls, says, "Witch," and starts walking backwards towards the front door, pulling Stiles with him. "You have until sundown to leave my territory. If I ever see you here again, I'll kill you. If you ever so much as think about touching Stiles, I'll rip you into pieces so small that your coven won't be able to stitch even a quarter of you back together."
Before Cordelia has a chance to respond, Derek's got Stiles in his arms and they're running from the house. Stiles closes his eyes, sinks into the safety and security of his pack bonds, and passes out.