Derek knew Stiles because he paid attention. He paid attention every waking moment. He knew that when he was nervous, he liked to talk and keep his hands busy. He swore when he had other things to say, he made his dad eat healthy because of one bad test result, he tripped over his own feet more often than not, he knew how to shoot a gun.
Derek knew the face that Stiles made when he was tired, knew how the place between his eyebrows creased when he was angry, knew how his eyes got wide when he was interested in something.
He knew all of the noises Stiles made when Derek kissed his neck, when he drug his lips across the planes of Stiles' body, scraped his teeth over the skin, fingers feather light as they mapped his mate completely.
He also knew that when Stiles dropped face first onto the bed, barely bothering to toe his shoes off first, he was exhausted. Derek took his time getting the covers out from under Stiles' body, careful not to disturb his sleep. After that, Derek scooped up Kitty from the foot of the bed and made his way down the stairs and into the living room. Kitty, unhappy with having been moved, meowed pathetically before sauntering away.
Stiles had been going non-stop since Thanksgiving, prepping for exams and finishing papers and projects for the end of the school semester. With that and the constant research and police scanner vigilance about the last set of rogue betas that came through Beacon Hills, Stiles wasn't getting a lot of time to himself. Derek sacrificed his own rather dwindling time between his appointments around town to take care of Stiles.
Not that it was a big sacrifice to make. Stiles didn't seem inclined to take care of himself. He was too focused on everyone else, on pleasing everyone that he often forgot to take a moment for himself.
Derek ducked into the library, powering down the desktop and stuffing the research into drawers. They'd gotten into the habit of Stiles passing out for a few hours after homework before Derek would wake him up and follow him home.
The sheriff appreciated Derek's diligence on the matter.
It felt domestic, even if they only spent a few hours in one another's company these days. There was only a week left before the Christmas holiday for the high schoolers. And then they had two weeks off for the holiday before they started it all over again.
Kitty mewed pathetically from the doorway, understanding that she wasn't allowed in the library finally. Derek eyed her from his place at the desk before heaving a sigh, a show of defeat he'd keep in if anyone was there to see it, before marching to the hallway and looking down at the cat.
He hadn't been keen on the idea when Stiles first brought her home. It really didn't help that she seemed attached to Stiles and refused to let Derek near his boyfriend. But while Stiles was gone for his relative's funeral, there had been a moment of clarity between Kitty and Derek.
Not that Derek was ever going to admit that he'd been cowed by a kitten, but it had happened. She was small and it was his house, but Stiles was a little in love with her and Derek couldn't imagine ever getting rid of her now.
Kitty rubbed against Derek's leg, walking figure eights around his feet so fast that Derek was getting a little dizzy watching her, before she sat down and mewed at him again. He bent down, scrubbing a hand down her neck and back, pausing as her back lowered and she started to meow continuously.
He scented quickly before a scowl crossed his face and he swore. Damn cats. Damn cats and damn animals.
Just Derek's luck that Kitty would go into heat this early.
He was contemplating picking the cat up and throwing her into the laundry room just for the hell of it when he heard a pair of feet on the floorboards over his head. He mentally tracked their movement, from the bedroom to the bathroom before making their way to the stairs, before he glanced back down at the cat.
"I'll deal with this later."
He checked his watch before shaking his head. Stiles was up earlier than usual, not that Derek was going to complain. He stepped around the cat and made his way into the living room, fighting a smile at the stumbling mess that was his boyfriend.
"You're up early." Stiles tripped down the last few steps, catching himself on the railing at the last minute, before stumbling over to where Derek was standing and pressing his face against his neck.
"I don't need to go to college. I can drop out of school and just be your kept boy, right? That's a plan. Dad always says I need a plan." He yawned out the last sentence, snuggling further when Derek wrapped his arms around his waist.
"I don't think that's what your father had in mind when he said that you needed a plan for the future Stiles." Stiles made a noise in the back of his throat, probably in deference, before pulling back to smile.
"Thanks for letting me cat nap." Derek tried not to snort at that, shaking his head and pulling back fully.
"Speaking of cats." He knew his voice had dropped almost to a growl, but he didn't care. Stiles made grabby hands at Derek, clearly wanting to return to their standing snuggle, but Derek steeled himself.
"C'mon, I thought we were over letting Kitty disrupt our alone time?"
If there was one thing that would almost always work on Derek, it was a guilt trip. He allowed Stiles to corner him back into a hug, unable to help himself nuzzling against the short hair that Stiles seemed to favor.
"She's going into heat." Stiles snorted against Derek's neck at that, pulling back to look down to where Kitty had started to rub along their legs.
"You're joking." Derek glared first at Kitty and then up at Stiles.
"I can smell it on her." That caused Stiles to bend over in laughter, barely keeping hold of Derek as he fought with the giggles.
"Oh, oh, I'm sorry, but you gotta admit, that's pretty hilarious. Oh come on sourpuss, it's not that bad."
They glanced down at the meows and watched in mutual horror as Kitty started to rub her back end against Stiles' shoe.
"Oh. My. God."
A phone call at four in the morning was never a good thing. Derek rolled over, hand slapping hard against the bedside table as he looked for his phone. He grabbed the device just as it started to vibrate off of the table.
"What?" His voice was rough, testament to how little sleep he'd gotten. There was a pause on the other end and Derek pulled the phone back to glare at the ID before he realized who it was.
"Sheriff?" It was never a good thing when he got a late night call from the sheriff. And it wasn't his boyfriend's dad right now, because he'd learned to do what Stiles did and separate the two entities.
"Sorry to wake you, Derek, but I think you'd better get down to the station."
Derek had already gotten up and was finding clothes to pull on, so he told the Sheriff he'd be there in ten minutes. Once he was dressed, he glanced down at Stiles' sleeping form. He hadn't even budged during the commotion. He pressed a kiss to Stiles' shoulder, slipping out of the room and down the stairs silently. He wrote Stiles a quick note, taping it to the railing of the stairs before grabbing his keys and slipping out.
Outside the wind was harsh. Derek hadn't bothered grabbing more than his clothes, so he fought against the cold as he slid into the Camaro and drove off. He didn't bother with the heat knowing it wouldn't kick in until he'd pulled into the station.
It was easy to spot the sheriff leaning against the wall of the building. Derek shut off his car, steeled himself for the cold, and made his way over to him. Mark shook his head at Derek's clothes, a t-shirt and jeans in early December.
"I'd tell you we could go inside, but this conversation needs to be off the record. I would have driven out to your place but I know Stiles is there."
Derek didn’t bother commenting on that, even though Stiles had sworn that he had snuck out without getting caught.
"What's going on sheriff?" The sheriff glanced over his shoulder as if he was looking for someone, but Derek knew no one else was outside with them. He focused on the sheriff and pushed his chilled skin out of his mind.
"We've been getting some reports, few calls a week, about animal attacks. It's bringing back the hysteria of last year, but so far we're keeping everything low key."
"You're thinking werewolves." He didn't bother beating around the bush. If the sheriff was calling him out at four in the morning, it was past the point of hints and subtly. The sheriff nodded, looking exhausted and tired in a way Derek hadn't seen since the last time his son's life was in danger.
"I've had a few chats with Chris Argent who told me that all signs point to betas without a pack. After assuring me it wasn't one of my son's buddies out causing chaos, he told me I should be the one to talk to you to remind you of the truce you have with Argent."
Derek nodded, senses flickering behind him as he heard someone leave the station and get into a car to drive away. He didn't wonder if they saw him and the sheriff in the corner. They were well hidden by the shadow of the building.
"Okay, so what is this, you just letting me know that there are some unclaimed betas in town, or are you asking for my help?"
They already knew about the betas, although Derek was sure they'd run them out of town. He'd have to talk to Stiles, see if they missed something. Especially since the betas they were tracking weren't really violent, just seemed lost and a little uncaring if people found out about them being werewolves.
"Little of both. As much as I don't want anything to happen to my son, I also know that letting Chris Argent think he has the run of the town just because he is a hunter isn't going to work. There are only so many times he can save the day with that small arsenal he owns before the media starts thinking we've militarized our citizens."
Not that they weren't all grateful for Chris and his keen ability to be present for most troubles. He'd saved everyone's asses at least once at this point.
"You're asking me to find and neutralize the issue?" Derek listened to the sheriff's heartbeat, noting with a vague sense of detachment that the sheriff seemed okay with everything that he was asking.
"I'm asking you to do what it is you do best and protect the town." Derek shook his head lightly.
"I'm not the cities protector, sheriff. I'm just protecting my own."
His pack. His mate. Mark seemed to get that, seemed to understand that everything Derek had done had been in part for his son, because he nodded soberly and then zipped his jacket up a bit.
"Alright. You should get home. I know for a fact that if my son wakes up and you're gone, he's going to get into trouble." Derek didn't bother refuting that. He knew it just as well.
After saying goodbye, Derek made his way to the Camaro and slipped away from the station unseen. His house was just as dark as it was when he left, save the porch light that he didn't turn on. He fought back a shiver as he stepped through the door, instantly warming. The note was gone, but there was no sign of Stiles besides those two differences.
He made his way up the stairs and into his bedroom, amused at the fact that Stiles had curled up on Derek's side of the bed. He shed his clothes before slipping under the covers, careful not to press any frozen body parts against Stiles, but it was in vain. Once Derek's body had touched the bed, Stiles had uncurled and scooted over to where Derek was.
"Mm, cold." Derek laughed as he wrapped an arm over the blanket and pulled Stiles closer, comfortable in the sleepy heat that rose from him.
"Go to sleep."
He'd been tracking the beta for thirty minutes. Thirty minutes of moving as quickly and quietly in the woods as he could manage, having shifted into full alpha to make it easier. Scott and Jackson were close behind, spread out to cover his flank. Danny and Lydia were off to either side, keeping their eyes open for any movement.
Allison and Stiles were together near the road, each armed with their bows. Stiles had gotten really attached to the crossbow he'd used in their battle at Derek's house so Allison had talked her dad into giving it to him.
That had probably been an interesting conversation, but Derek didn't let himself dwell on it.
There was a movement in front of him and his eyes snapped forward, mentally berating himself for getting so out of focus. There was someone out there, their body distorted by the snow that was falling. Derek moved quietly, wanting to use surprise to his advantage, but he stopped short.
The body in front of him was no long distorted. It was shifting, but not like a werewolf. It was there, folding in on itself, and then Derek was looking at... Stiles?
He felt the growl rip through his throat before he could stop it. Whatever it was, it wasn't a werewolf. It'd taken on the visage of Stiles, which meant it either knew who Derek was or it was mirroring Derek's thoughts. Either way, Derek launched himself at it, but stopped short.
Stiles looked terrified of Derek, eyes wide and mouth panting out short bursts of warm air.
"Don't... please don't?" Derek felt his heart tug, unable to force himself to attack his mate. Even if it wasn't his mate, which just tripled the anger he felt, because some thing was manipulating his mate's image, but he couldn't do it.
The rest of the pack was coming up behind him, but they all stuttered to a stop at the sight of Derek, one arm raised to slash at Stiles, and Stiles shaking.
"What is..." The creature turned to look at Danny who had spoken before opening his mouth almost too wide, teeth elongating and hissing at the group, flipping his body out of human abilities and running through the forest, body elongated and stretched into a horrible facsimile of human.
The pack raced after it, trying to get ahead of it and cut it off, but it was faster than they were and soon they lost the track. Lydia, the only one that didn't shift like normal betas, looked distressed in a way the other werewolves couldn't portray in their current states.
"What was that thing? How did it... it looked just like Stiles!" Derek growled, still in his alpha state.
"Whatever it is, we'll figure it out."
They raced back to the road, making it there quicker than they'd thought possible. Allison and Stiles were aiming towards them, but when they saw that it was the pack, they lowered their arrows and sighed collectively.
"What's going on? We get him?" Derek shook his head, shifting back into human and grabbing the pants that Stiles had thrusted at him. He couldn't feel the cold yet, there being too much adrenaline still pumping through his body.
"No. It's not a werewolf." Allison turned from where she was hugging Scott to face Derek.
"What do you mean?" Danny stepped into the group, eyes on Stiles' as if he'd never seen him before.
"When we got to where Derek was standing off with him... it... it was Stiles. I mean, it wasn't him, but it looked just like him. He looked scared and... then it just warped out and ran off."
Stiles' jaw was hanging open but he snapped it close and turned to look at Derek for explanation.
"I don't know. We aren't going to figure it out tonight and he's not coming back tonight. We need to get somewhere where we can look this stuff up."
He didn't want to show that he was scared, but he was. Whatever it was, they could defeat it, but Derek remembered the horror he felt as he'd been about to slash the throat of his mate... but not his mate. No matter how much he knew it wasn't really Stiles, he couldn't bring himself to end the creature.
What if that was the purpose of the shift?
Derek shook his head, trying not to meet Stiles' eyes as they all piled into their cars to head to his house. They'd figure it out. They had no choice.
Christmas was in less than a week. The house stayed warm and occupied, with at least one member of the pack there at all times. Derek didn't mind. The house felt lived in once more, in a way that it did when his family was still alive.
They'd done as much research as they could on the thing they'd run into in the woods, but very little had come up. They were people, or they had been once. They could take on other appearances, but when faced with danger, it mirrored the subconscious of the person they were fighting.
So when approached by an angry Derek, it mirrored his subconscious to the one person he couldn't hurt.
Stiles had found that undeniably romantic and had spent the next few hours showing Derek just how much he appreciated it. Derek had no objections.
They'd told the sheriff and Chris what they knew, neither one very happy with the news. It wasn't a werewolf but some creature they knew nothing about.
There hadn't been any more sightings at least, which was good. Since their tangle in the woods, the creature had stayed off the radar. Maybe seeing that there were other supernatural beings in Beacon Hills had sent the creature running somewhere else.
Stiles had been secretive for the past week, going as far as keeping his bedroom window shut and locked when he wasn't at the house. Not that Derek tried to sneak into his room to figure out what was going on.
Just that once.
It came to a head on Christmas Eve, with Stiles curled up with Derek on the couch while watching an old black and white film. Derek would be joining Stiles at his house in the morning for Christmas breakfast and presents, joined by the rest of the pack at some point during the day for more presents, but Derek had persuaded Stiles to join him the night before for some alone time.
Stiles had been antsy the entire night, casting a glance to the clock more often than not. Derek would be insulted, but he had a feeling he knew what was going on.
Once the clock struck midnight, Derek was deemed right.
"Okay, so it is officially Christmas. I don't want to wait, so let me... be right back." He ran out of the living room to the study. Derek waited for him to return, curious and a little anxious.
Stiles returned with a box in his hands, wrapped a little awkwardly with a bow on top. Derek raised an eyebrow at it but didn't say anything as it was placed in his lap. He pulled off the wrapping paper before lifting the lid of the box.
Inside was a photo album, almost exactly like one of the ones that had burned in the fire. The pictures inside had mostly been salvaged save for a few that were burnt along the edges.
Derek flipped it open, looking at the images as the showed the progression of his family. He flipped until the pictures were no longer of his family but were now of the pack. Stiles had merged the two, making it so that you couldn't see where one family ended and the other began.
"Thank you." His voice was low, rough against the emotions he was holding in. Stiles sat down beside him and pressed his lips against his temple before Derek pushed the book onto the coffee table, pulling Stiles to him tightly and claiming his lips.
"Mm, this is quite the thank you." Derek laughed, combing his fingers over the back of Stiles' head and pulled him down for another kiss, softer this time.
"I didn't have the time to wrap your present." Stiles pulled back, eyes glassy as he tried to focus on Derek's words.
Derek reached into his pocket and fumbled around for what he was looking for. Once he found it, he pulled it out and pressed it into Stiles' hand.
He watched as Stiles looked first at the object in his hand and then to Derek's face, back and forth as if he couldn't decide which to settle on.
"Derek?" Derek looked down, curling Stiles' fingers around the key in his palm.
"Your dad won't approve of you moving in with me until you're eighteen and out of high school, but this is for that time."
He waited as Stiles stared at his fist, the key no doubt pressing against the skin there, but he didn't have to wait long. Stiles launched himself at Derek, wrapping his arms around his neck and hauling him in for a deep kiss that almost tilted them off balance.
There was a laugh, torn from deep inside Stiles as he straddled Derek. At first Derek wasn't sure what caused it until he lifted his head and saw Kitty on the couch beside them, beside herself as she rubbed against Stiles' leg.
"You know, I was reading online where it said that you can bring her out of heat using a q-tip and--" Derek pulled Stiles forward, crushing the words between their lips.
"I think I know where the rest of this sentence is going and the answer is no. I don't need her following either of us around more than she already is."
Stiles laughed again, pushing the cat off of the couch as he moved closer to Derek, pressing his lips to the space between Derek's jaw and shoulder, biting down lightly.
"Merry Christmas, Derek."
Derek didn't reply, simply squeezed Stiles' hips. He didn't need to say it back, but he never needed to say those things. He said them with actions.
After Christmas breakfast at the Stilinski household, which had been interesting and terrifying in turns, Derek and Stiles had gone back to Derek's house to wait for the pack. They hadn't been able to decide on a set time to meet up but instead would trickle through whenever they were free from familial obligations.
Lydia was the first one to arrive. She'd come in with her shoulders tense, eyes wide but not really taking in anything. A car in the driveway honked, a goodbye, and it seemed like the moment the car was out of the driveway she relaxed.
Her home life left much to be desired these days, or so it seemed. Derek didn't press the issue, knowing that some things needed to be kept away from the pack for her own sanity, but she knew they were all there for her.
"You give the key to him?" Derek glanced over at Lydia, unimpressed that she knew about his plan. She seemed to always know things before everyone else. It'd long ago lost the ability to startle him.
"Last night." She made a cooing sound, eyes straying to where Stiles was curled up on the couch with newspapers from other cities.
Even on Christmas, he never took a break.
"Can I talk to you? In private?" Derek glanced over to where Stiles was, only a few feet away but completely immersed in his research. He nodded, pressing his hand to Stiles' shoulder to let him know they'd be back, before following her onto the back porch.
There was a thin layer of snow on the ground, a dusting more than anything, but it made the woods surrounding the house look oddly majestic. Lydia ran her fingers over the picnic table, creating designs in the snow there.
"When we came across that creature, you couldn't attack because it looked like Stiles." It wasn't a question, it wasn't an accusation, it was simply a statement of fact.
She didn't wait for him to respond before he continued.
"It wasn't just because it looked like Stiles though, right? Because it bore a threat to the pack and you as the alpha take that seriously. No, the reason you couldn't attack wasn't because it looked like Stiles, but because it looked like your mate."
He saw where this was headed. Derek moved over to where Lydia was standing, subtly scenting the air around her before smiling.
"You and Jackson are thinking about mating?" She shrugged, although he could hear her heart picking up the pace.
"We're thinking about it, yeah. He didn't feel comfortable asking his alpha for relationship advice, despite the fact that you're the only one that would understand it. I think it has more to do with not wanting to know anything about yours and Stiles' relationship. I, on the other hand, already know the details so it doesn't bother me."
Derek didn't react, although he was sure that's what she was aiming for. Instead he sat down, pulling her onto the snow covered bench beside him.
"It is something Stiles and I have been dealing with for months before we acknowledged it. The connection, although maybe not starting because we were mates, connected us almost the same way. I could feel him, felt different around him. We had time to get used to it. When you first bond that way, it's... overwhelming. You see and hear and feel things from yourself and from his side."
Lydia twisted on the bench until she was facing him as much as she could.
"What did it feel like, when you realized you were about to attack someone that looked like your mate?"
Derek thought about it, thought about the night he spent way too much time thinking about as it was. He could remember the tension in his arm as he tried not to swing at his mate's face, the horror on the not-Stiles' face, the constriction in his chest as his mind and his wolf battled.
Stiles was always in trouble. It wasn't because he was human; it wasn't because he was Derek's mate. It was just Stiles. Derek knew that if Stiles ever got the bite, it'd be much the same. But that Derek had, even for a moment, thought about tearing his throat out...
He fought off a shiver, not wanting one of his betas to see.
"It was something I will never forget, but it will have to be done. If it happens again, I will have to do what must be done."
He didn't want to have to think about it, what it meant that he might have to attack and kill something that resembled his mate. As the alpha, he would have to push through it. He would prepare in any way he could.
"I'm scared that things will change if we mate." Derek glanced over at Lydia, taking in her sheltered look before he reached across and squeezed her hand. It broke her out of her reverie and she looked up at him, a smile almost on her lips.
"Things will change, but if you and Jackson are meant to be mates, and you'll know if you aren't, it will change for the best. No matter what, it won't change the amount you love one another. You'll feel that all the more."
Lydia nodded, glancing at the backdoor where she could see Stiles moving about in the kitchen with Scott, laughing and playfully tackling each other. Danny was leaning against the doorway shaking his head while laughing. The rest of the pack was either in the living room or still on their way.
"It's going to be okay, isn't it?"
Derek didn't respond, simply helped Lydia up and walked her back into the house. The others greeted him before going back to their activities. Stiles separated from Scott long enough to sidle up beside Derek, running his fingers slowly over Derek's arm.
"Everything good?" Stiles' voice was calm, open. It was something that Derek loved, knowing that Stiles trusted him that much.
"Yeah, everything is good."