Derek doesn’t care. Really, it doesn't bother him at all.
At first, he only sees Stiles do it with Scott. The boy is happy about something, like he always is, excited, and he jumps at Scott and plants a probably wet kiss on his cheek. Scott doesn’t react like Derek expects him to, he doesn’t grimace or push Stiles away. He just grins, like this is normal, this is what they do.
Derek doesn’t realize how much that’s true until later, when he sees Stiles kiss Allison. The pack is meeting up at Derek’s house, like they do now and then and Allison brings cookies that her mom made. She calls them triple chocolate peanutbutter cookies and apparently that means something to Stiles because his whole face lights up like fireworks and he quickly takes Allison’s face in both hands and kisses her on the lips. Just a short, sweet, happy kiss, barely more than a peck, but Scott is right there watching the whole thing, smiling, and Derek wasn’t aware that it was normal for a guy to kiss his best friend’s girlfriend.
But maybe they are really good friends, Derek reasons. Maybe Scott just doesn’t mind because he knows that Stiles is impulsive and will sometimes do things that can’t be explained. Maybe.
Stiles doesn’t kiss Danny or Lydia, Derek notices soon and it backs up his theory. There’s no doubt that Stiles and Danny like each other, they joke around all the time and Stiles sometimes comes to a pack meeting with Danny’s scent all over him because they played video games all night. Then the two bicker all day because Danny apparently beat Stiles at every single one and Stiles thinks that should give him nerd status.
But while Stiles doesn’t kiss Danny, they touch more than Derek thought was normal. They hug and put their arms around each other when sitting, they lean against each other on every occasion and they stand entirely too close when Stiles is cooking in Derek's kitchen and Danny has to taste it to see if it's too spicy because Jackson will bitch at Stiles all through dinner if it is but refuses to try Stiles' food himself before he sees someone else eat it.
When Derek sees Stiles plant a kiss on Jackson's temple – comforting, because the US national team just lost the World Lacrosse Championship -, it stops making any kind of sense and he asks Allison about it. He figures she's the one who definitely won't laugh at him.
„So, what you're asking is, why does Stiles kiss people all the time? Or just why doesn't he kiss you?“ Allison asks, her eyebrows raised in general confusion. „If you want him to kiss you, you could just- I don't know, ask, probably...“
Derek gets the hell out of there and doesn't ask her again.
He still watches, though and if anything, it gets worse.Stiles kisses people all the time. Never more than small pecks, definitely sweet and platonic but Derek can't help but wonder. And comment.
„Stiles.“ he interrupts one day. „Can you stop kissing Jackson for a second and help me bring the groceries in?“
He doesn't mean to make it come out as it does, annoyed and disapproving and he doesn't need help with the groceries either. But Stiles jumps up like he's been bitten and grabs one of the full paper bags to carry them into the kitchen.
„What are we making for dinner?“ Stiles asks, unpacking the bags and storing things in cupboards, following a system Derek doesn't understand.
„Danny wants pasta.“
„Oh, can we make meatballs too?“ Stiles' eyes widen. „I love pasta with meatballs, you have no idea. Mom used to make that for my birthday ever since I saw the movie because I liked it so much. And then for dad's birthday too. And her birthday too, actually-“
„It's not your birthday.“ it just kind of slips out, Derek didn't even think of saying it. But Stiles face falls a little and he quickly turns back to the fridge, storing milk and eggs away.
„We didn't buy any ingredients for meatballs.“, Derek adds, like that makes it any better.
„Yeah, okay.“ Stiles nods, his voice a little squeaky, like it gets when he's either very excited or upset. Derek puts his bet on the later. „Just tomato sauce then? Danny can make it, he makes great tomato sauce.“
„Okay. I have to go out again, I'll be back soon.“ Derek says and leaves Stiles to put the rest of the groceries away and find the bag of chips which he'll eat before dinner, Derek knows.
He finds Danny in the living room, lounging on the couch with Jackson's head in his lap, asleep.
„I'm going back to the grocery store, Stiles wants meatballs.“
Danny doesn't really look surprised, just nods and keeps stroking Jackson's hair when he stirs in his sleep.
It's miserable outside, rain pouring down from the sky like nobody's business and Derek briefly regrets his decision. He’s as far from touchy-feely as it gets, the complete opposite from Stiles, it seems, and he has no desire to suddenly start kissing people as well. He’s not sure why he cares so much, why it even caught his attention. Enough that he goes back out to buy more food they don’t need, just because Stiles might have had tears in his eyes just now and he’d rather see happy Stiles kissing people than that.
And it feels worth it when Stiles enters the kitchen right when Danny starts unpacking the ground meat and his eyes light up. He glances over at Derek, surprised and a little disbelieving and with the kind of happy-confused look that only Stiles has.
„Meatballs!“ Stiles exclaims finally and grabs the bowl from Danny, mashing the ground meat in it. „I'll make them, I'm a pro.“
„Hey, wash your hands first!“ Danny protests, taking the bowl back. Derek watches for a moment, then leaves to bully Scott into setting the table.
Apparently, meatballs aren't enough to get a kiss from Stiles. Not that Derek was hoping for that.
- - -
„He's probably scared that you'll kick his ass for it.“ Lydia says quietly, stepping into the kitchen to help him with the dishes. Although in this case, helping means watching and handing him things because Lydia refuses to ruin her nails with dirty water and dishsoap.
„I don't know what you're talking about.“ Derek lies. It's not really any of her business and when did all of this become public knowledge anyway?
„Allison told me.“ Lydia shrugs. „He doesn't mean anything by it, he just thinks you won't like it. I don't know why he thinks that, it's obviously you'd like it.“
„What?“ Derek frowns in confusion.
„You don't have to pretend, I already know you like Stiles. I can't blame you.“ She hands him the last dirty plate with a smile, not bothered by the low growl that escapes his throat. „Don't growl at me, I don't like Stiles like that. I'm just saying, you'd probably never get bored with him.“
She turns to leave the kitchen, stopping in the door and turning around again like the drama queen she is. „If he won't kiss you, maybe you should kiss him first?“
The plate slips out of his hands for no reason at all and crashes to the floor, breaking into tiny pieces. Stiles skitters into the kitchen, alerted by the noise and starts panicking over a possible attack by hunters until Derek calmly takes a glass, fills it with water and splashes Stiles' face with it.
After that, they all settle in front of the TV.
- - -
Derek doesn't take Lydia's advice, of course not. It's terrible advice. But it stays on his mind, because Stiles keeps kissing and touching people and Lydia's words made an impact. Is Stiles still that afraid of Derek? They've been a pack for months and it's not like Derek actively tries to threaten anyone anymore. It's not his fault that he's intimidating by nature.
So he doesn't take Lydia's advice but he tries to be less intimidating. He fails spectacularly, especially on Stiles' birthday, two months later, when he squeaks in fear as Derek hugs him. It takes him a moment to stiffly return it but it's better than nothing, so Derek takes it.
And at least he remembered to have Danny make pasta with tomato sauce and meatballs. He figures he deserves some credit for that.
They clean up a huge pile of pasta between the seven of them and then there's ice cream with cheesecake dough in it – Derek doesn't have to understand it in order to eat and enjoy it – which is Stiles' favorite as well, apparently.
After that, it's time for presents. Or, one present, because they all made it together. It was Allison's idea and she made sure it actually worked out. They started several weeks ago so it'd be ready in time.
It's probably the cheesiest present they could have come up with, but they are all leaving for college soon and they don't know whether they can stay together like this for much longer. Stiles looks very happy as he opens the photo album and finds as many pictures of the pack as they could fit in the book.
Scott and Allison sitting on the porch of the Hale house, Jackson sleeping in the backseat of Stiles' car, Danny and Stiles geeking over sci-fi movies, Derek reading a book, Lydia tying her hair to a ponytail and many more. Pictures where they posed for the camera, arm in arm or making silly faces.
There are also a few pictures Derek doesn't know, of Scott and Stiles when they were much younger. Derek doesn't have to ask to know that the woman in some of those pictures is Stiles' mom. Stiles looks a lot like her.
Danny had to bring his camera wherever they went to take this many pictures and Scott annoyed the hell out of his mom to find the old photo albums she had stored away in boxes in the basement.
It was worth the effort, no question about it.
Stiles starts with Scott, planting a kiss on his cheek. Allison gets one on the lips. He hugs Lydia, kisses both Jackson and Danny somewhere on their faces where he can reach and then Stiles stops short when it's Derek's turn.
„Hey, thanks. For the present. It's great, I love it.“ he says, awkwardly hugging the album to his chest. „I thought something was up when Danny kept taking pictures but-“
„Seriously?“ Derek's had it. He's just had it. What is he, chopped liver? He's the alpha of this pack. „That's all?“
„Um.“ Stiles looks like he's just swallowed his tongue. „What do you- all of what?“
Fine. So what, if he's taking Lydia's advice? If it blows up in his face, at least he has someone to blame.
Derek dips his head down to kiss Stiles' on the cheek, just like Stiles does with everyone, a little peck that means absolutely nothing but friendship. But he hasn't counted on Stiles moving his head towards him and raising his chin, so that his lips land on the corner of Stiles' mouth, soft with surprise. He also hasn't counted on Stiles' reaching up, wrapping one hand around Derek's nape, the other one around his waist, and pulling him closer with surprising strength.
Stiles' lips part a little, Derek automatically follows suit and suddenly, they're really kissing.
He hears Allison gasp and then giggle and Lydia makes that triumphant huh that he hates. The gagging sound may come from Jackson, Derek's not sure and he doesn't care because he's kissing Stiles.
When they break apart after long moments, neither of them ready to face what just happened, no one says a word. They kissed in front of the entire pack, an awkward, amazing, surprising kiss, and neither one of them can pretend they didn't want it.
„Um. I don't actually know what just happened. Give me a minute, I'll figure it out.“ Stiles stares at Derek like he's just grown a third eye.
„Okay.“ Danny replies instead. „I'm gonna go to the kitchen, to the other room, to eat Stiles' birthday cake now. You guys feel free to join me. Now.“
He turns to walk away and makes sure to grab Jackson's wrist and pull until Jackson yields, stumbling after him; the others are more than ready to follow. Lydia looks just as smug as Derek expected and it will probably take a long time of teasing before she'll let this one go.
Derek doesn’t care. No, really, this time, it doesn't bother him at all.
He figures he’ll get a lot of kisses from Stiles from now on.
Not that Derek was hoping for that.