This started out as a paragraph long drabble but I got a little carried away. Right now it's a stand alone piece, but I may come back and add to it in the future.
"There, all fixed." Stiles checks the bandage on Derek's arm. "Well, not fixed, but it should start healing on its own soon."
Derek had climbed through Stiles' window at 11 pm, bloody and exhausted from a surprise visit from the Alphas that he apparently didn't see fit to call the pack about, and after several minutes of heated debate Stiles noticed that the wounds weren't healing. He pushed Derek into the bathroom and set to cleaning him up. He'd been working with Deaton after school several days a week and had learned quite a bit about healing and werewolves. He had even invented a salve especially designed to speed up healing, and it had proven popular within the pack given the amount of injuries sustained from the Alphas.
Derek is oddly reticent as Stiles cleans the wound and applies the salve, but Stiles decides not to push it. He's just checking the bandage when Derek asks him, "Can I stay here for the night?"
Stiles looks up, surprised.
"What do you mean 'can you stay here?' This is the Sheriff's house!"
"I mean," Derek begins, patronizingly slow, "Can I stay here?"
"Why not ask Scott, or Boyd, or Erica, or anyone who is not me?" Stiles punctuates his sentence with flailing arm gestures.
"I'm already here. And anyways, Scott hates my guts-"
"No, he strongly dislikes you, there's a difference."
"Yes, well, thank you for enlightening me. As I was saying, Scotts a no, Boyd's parents are around too much, and Erica..." Derek trails off, looking uncomfortable.
"You're seriously afraid of Erica?" Stiles asks, incredulous.
"It's Erica! Everyone's afraid of Erica. Plus I don't want her trying to kiss me again."
It's true though, Erica could be frightening when she wanted to be, which was basically all the time.
"Okay, fine," Stiles says.
"Is that a yes?" Derek has this adorable hopeful look on his face, and Stiles never would have thought Derek to be one for the puppy eyes, but it doesn't seem intentional and oh god he's going to regret this.
"Yes, you can stay here."
Derek starts walking back towards the bedroom, stripping off his shirt as he goes, and Stiles is momentarily distracted by the blinding perfection that is Derek Hale's abs. But only momentarily.
"What do you think you're doing?" Stiles asks, following behind him.
"Getting ready for bed, it's close to midnight and I'm tired."
"Oh. Wait, you're not sleeping in my bed!" Derek just raises an eyebrow and pulls back the covers. Stiles sputters. This is not what he agreed to, damn it. Sharing a bed with Derek is only going to lead to awkwardness and boners, and while in another context (that Stiles has not thought about, not at all) sleeping with Derek would be a very good thing, Stiles can tell this is not going to end well.
"Stop glaring at me and get in already." Derek mutters, and Stiles reluctantly follows suit.
It takes him a long time to fall asleep, mainly because he's hyper aware of his body in relation to Derek's. Maybe it's just the extra heat werewolves give off, but it feels like Derek is super close. Close enough to smell Stiles' anxiety at any rate.
"Calm down."
"I am calm."
"Even if I couldn't hear your heartbeat I would know that that's a lie."
"We have an unknown number of Alphas on the loose and there's a werewolf in my bed, of course I'm not calm. I'm the opposite of calm. I am very far away from any state resembling calmness. I am so far from calm that-" Derek cuts him off
"Come here." Derek wraps an arm around Stiles and pulls him close, until Stiles can feel Derek's breath on the back of his neck. Derek places a hand over Stiles' heart and it must be some sort of werewolf superpower or something, but Stiles can feel his pulse come back to normal.
"Better?"
"Better."
"Goodnight Stiles."
"Goodnight sour wolf."
Stiles wakes up with an arm slung over his stomach and stubble scratching at his neck. Derek's breath is warm against his skin. It's strangely domestic but not uncomfortable. Stiles imagines waking up to this more often and finds the idea not unpleasant. Okay, that may be an understatement; the idea of waking up with Derek fills his chest with warmth and contentment and a feeling that he will have to examine at a later point. Right now he's comfortable though, and he burrows back into the curve of Derek's body, not caring that he has school in an hour.
Things start changing after that. Stiles catches Derek looking at him sometimes, and the heat in his gaze makes Stiles blush and turn away. Derek is also more tactile, in a way that he probably thinks is subtle but actually has the pack making faces at each other. It doesn't take long to realize that Derek's new-found affectionate side is pretty much limited to interactions with Stiles.
Derek shows up in Stiles' window again a few weeks later, this time without any obvious injury. He and Stiles work on the bestiary for a bit before Derek migrates to the bed. Derek is once again the big spoon and Stiles has to bite his cheek from saying anything about the big bad alpha liking to cuddle.
The third time it happens Stiles starts to think that maybe this means something, that Derek is actively seeking him out like this, trusting him enough to sleep beside him.
He knows they have to talk eventually, he and Derek are doing some sort of weird dance around each other and Stiles is pretty sure he heard Erica say something about locking the two of them in a room until one of them jumps the other, but he doesn't know how to bring it up.
Derek has once again spent the night. They're tangled together, and Stiles is drawing designs on Derek's chest with his finger. He's spelling out 'sour wolf' when Derek breaks the silence.
"I can feel you thinking." Derek murmurs. It's still early, and Stiles has some time before he has to get up.
"I just think that we should talk."
Derek props himself up on his elbows and looks down at Stiles. Stiles doesn't know what Derek's looking for, but he seems to find it because the next thing he knows Derek is leaning down and pressing his lips against his. It's chaste, really, but it seems heavy with meaning. Derek pulls back after a few seconds and gives Stiles that look again, the one that makes him blush and turn away. Only this time he meets Derek's eyes.
Stiles is about to suggest they can talk later, but as soon as he opens his mouth Derek is kissing him again and this is good, very good, definitely time for talking later, more kissing now, and Stiles thinks he may have said some of that out loud because Derek huffs a laugh.
"What does it take to shut you up?" Derek says, smiling fondly at Stiles.
"I don't know, why don't you find out." Stiles tries to look suggestive but judging by Derek's face he fails. It doesn't matter though, because Derek has a determined look about him now and he's moving down the bed and oh yes that's good that's very good keep doing that I'll shut up now.
Stiles doesn't shut up, but Derek finds he rather likes the commentary.