Stiles isn't sure why he thought this was a good idea. It's not like trolling around the halls of Beacon Hills High after sunset has ever wrought anything substantial. Unless you count more fodder for nightmares as something substantial.

"Not sure why you had to come with me to sniff around for clues. It's not like you're going to be of any use." Derek grumbles and affects a bored stance.

The guy is gone for weeks with no word, and when he returns he's just as big of an asshole as when he left. Whatever secret soul-searching mission he went on was obviously a pointless endeavor.

"Right. No. Why would I?" Stiles says, trying to disguise the hurt in his voice with disdain. "So, I'll just take my copy of the master key to the school and be on my merry way then." He narrows his eyes in challenge and turns to leave.

Derek stops him with a hand to the chest, twisting the material of Stiles's new t-shirt around his fingers, just to be more of a dick. "You have a key to the...what am I saying? Of course you do. You probably have a key to my apartment, too."

Stiles looks away and furtively palms his keychain to hide it from Derek's view. The amount of ill-begotten keys he has hanging from the flimsy, metal ring in his hand is probably enough evidence to have him put away for the better part of his 20's.

"Goddammit, Stiles," Derek curses under his breath while shooting him an irritated glare.

His nostrils flare with the effort to control his temper, and Stiles mentally kicks himself for finding it as hot as he does.

"To be fair, you never specifically told me I couldn't have a key..."

Derek rolls his eyes so hard that Stiles legit worries the big guy might injure himself. "So, you're the reason my loft looks like a clown puked glitter everywhere?"

"Me?" Stiles jerks his thumb with so much force that his body goes along for the ride. "No, dude. I mean, I unlocked the door, but that was it. Danny and Ethan were the ones who trashed your house."

"Stay the fuck out of my place, Stiles," he growls while thrusting a finger into Stiles's chest, hard enough to knock the wind out of his lungs. "And my stuff. That includes everything in my car, too."

Stay out of his apartment? Derek has some nerve making that demand, considering he's been creeping into his and Scott's houses without a courtesy call for the better part of a year.

Good to know privacy only works in one direction in Derek's world. Is he fucking kidding with this?

"What? Are you worried I'm going to dip into your collection of chew toys or rearrange the three items of furniture you found while dumpster shopping?" Stiles cards through the heavy set of keys and locates the correct one by sight.

This isn't his first trip to the rodeo, so the process takes him less than five seconds.

"Or maybe you think I'm gonna steal your Luddite porn stash. You look like you could be into some weird shit...it's always the quiet ones...Oh. My. God. That's it!" he says, off the flicker of shock behind Derek's eyes. "You have a giant porn stash under your bed! Don't you, you horndog? Now I feel like an idiot for not checking down there. That is so unlike me."

"Stiles..." Derek says as a warning.

"Big ups to you for being the last man on Earth who still buys porn in print format."

Stiles is suddenly furious with himself for not snooping through Derek's shit when he had the chance. It could have been very informative. Like, he could have learned what kind of kinks the guy has. Important to know for reasons.

Seeing what a joyless asshole Derek is, Stiles figures his kink is probably missionary position with all of the lights off. Sexy.

But with his spotty dating history, who the hell knows? Based on his last two girlfriends, one might assume his interests even trend toward S&M and dubious consent.

Stiles actually laughs out loud at the idea of Derek as a sub. A flash of Derek naked, on all fours with a black, leather collar around his neck has him pulling at the neck of his own t-shirt in an effort to cool down the flush that is creeping up his skin.

"Really?" Derek's lips press into a sharp line.

Fuck those keen werewolf senses (he'd kind of like to, if he's being honest).

Whatever. He just made out with a hot girl tonight who totally wanted on his jock. How does Derek know the smell isn't just leftover arousal from that?

Stiles feigns an innocent look, which comes out looking more like constipation, because he hasn't been able to pull off 'innocent' since first grade. "I got lucky tonight. With a girl. That's what this..." he waves a lazy hand in the air. "That's what you think you're smelling."

"Okay." Derek's lips quirk with amusement.

Stiles realizes right after he says it, that emphasizing the word 'girl' makes his claim sound like absolute bullshit. He might as well have told Derek that he just made out with a girl he met at Summer camp in Canada.

He should stop talking about porn. If he had any survival instincts whatsoever, he would. But considering he's standing in the parking lot of his high school at 1am with a predator - whose teeth and claws rival a T-Rex's - looking for a gaggle of violent, tragedy-mask-wearing demons, safety is clearly not high on his list of priorities.

Plus, when has he ever given up a golden opportunity to rub Derek the wrong way?

Great. Now he's thinking of rubbing Derek the 'right' way.

Why did Caitlin have to put those kinds of ideas in his head? He was perfectly happy living in his cushy bubble of denial. It had served him well for the past 17 years.

Now, he can't stop the onslaught of wanton thoughts from rushing his brain - new and varied wanton thoughts - that alternate between the tickle of long red hair and a stiff brush of stubble rubbing against his thighs. It's like Caitlin ripped the regulator off of his love tap, and now his sink is bubbling to the top, threatening to overflow.

And now Stiles is apparently turned on by sinks. He did not sign up for this.

He presses the tip of the school's key against the swell of his bottom lip and faintly notices Derek eyes track the motion. Interesting.

"Based on my own personal experiences with you, Derek, I'm going to go out on a limb and assume that you like your porn rough...and hey, you wouldn't be the first." Stiles raises his hands in a preemptive mea culpa. "Though I'm guessing full on bondage is a no-go, because, you know...Kate."

Derek takes a step forward, nearly pinning Stiles against the cold, hard metal of the door handle. "Keep this up and you'll find out just how rough I like it. Personally."

WHAT.

The keyring slides through Stiles's fingers, but he manages to catch it just before it hits the ground.

Slick move, as usual.

Derek smirks and takes a step back as Stiles struggles to recover his dignity.

"I'm just gonna..." Stiles points to the lock and angrily shoves the key into the keyhole, failing to thread it the first two times.

He can feel Derek's presence just behind him, watching him, standing a little closer than usual but not so close that it's out of character. He always did have a problem with the concept of personal space.

The lock clicks and Stiles breathes out a sigh of relief. "See. Turns out you did need me, after all."

"Just get inside before you let the wraiths out," Derek says, in a tone that falls somewhere between a rasp and a hiss.

The rumble of it echoes in the pit of Stiles's groin.

Thanks a million, Caitlin!

"Not a sentence I ever thought I would hear." Stiles chuckles weakly and shoots Derek a lopsided grin before pushing his way inside of the building.


"Harris's old classroom, right?" Derek whispers, arching a brow in question.

"Yeah."

"Scott didn't say what I was supposed to be looking for. Just asked me if I would check it out for him and let him know if I see anything weird."

That's because Scott has no idea why they're there either. How was Stiles supposed to explain something he didn't understand himself?

"Lydia's mom replaced Harris as our chemistry teacher but is teaching biology class in there instead. That's pretty weird."

Derek shakes his head, his expression just this side of fond. "There are better things I could be doing with my time right now, Stiles."

Like thumbing through that vanilla porn stash under your bed?

"Then we should probably get this over with, so you can go do them." Stiles brushes past Derek in the direction of the classroom, but is stopped short by a firm grip on his bicep.

"What's going on with you?" Derek's forehead wrinkles as he strains to examine Stiles's face in the dim light of the hallway. "You smell-"

"You don't smell so hot yourself, Fido," Stiles snaps, yanking his arm from Derek's grasp.

The closer they get to the chemistry class, the stranger Stiles starts to feel. He's restless. His skin is pulled tight like a drum, restricting his movements. His insides are itchy, the organs within writhe like a festering wound.

Fear shoots through him like a thunderbolt and shivery sweat begins to bead on every surface of his body, collecting in the crevices. He helplessly watches his chest heave for air, but nothing passes in or out of his lungs. He is trapped in a flesh prison of his own making, without the possibility of escape or relief.

"Stiles!"

A name is called out, and Stiles recognizes it as his own, but can't form the words to answer.

He collapses against the outside of the classroom door, and his hands scramble for purchase on the thin sill of the glass pane that overlooks the room. He needs to get inside - is compelled to - it's why he came here tonight. He knows that now, just doesn't know why.

His vision blurs as the darkness begins to overtake his mind, inch by inch.

"Stiles..."

A strong pair hands lift him from the door, prying Stiles's fingers away from the handle as he grips for it in vain.

"Get off of me!" he is finally able to scream. "Get the fuck away from me!"

"No." Derek wrestles him to the floor of the hallway and straddles his waist, his knees pressing hard against Stiles's palms to pin him to the ground. "Snap out of it!"

A sharp slap stings the side of his face, but it may as well be happening to somebody else, because it barely registers. Another one follows in its wake.

Stiles bucks his hips in an effort to push Derek off of him, and nearly succeeds, until Derek shifts into beta form and lets rip with an earth-shattering roar, so loud it pierces through the fog in Stiles's head and shakes him from his stupor.

Derek pants hard, eyes vibrating with light, and holds his ground until Stiles's vision clears.

"D-derek..." he croaks, then shakes his head like a wet dog to rid himself of the cobwebs.

"Stiles?" Derek eyes him cautiously, and slowly releases his hands, but remains on top of him. "You're still in there, right?"

Derek never looked more frightened. Considering Stiles has seen him almost die on at least five separate occasions, that has to mean something.

"I - I don't really," Stiles's face crumples in despair, "I was in there the whole time, but at some point I-I wasn't alone."

Derek gently brushes the sweat-slicked hair from Stiles's forehead with his thumb. His intense stare is trained on him like a laser, even while his features recede back into human form. It's the softest his eyes have ever looked.

Being straddled by Derek is a fantasy he's had many times, usually with his hand wrapped around his own cock alone in the dark. But he could never let himself enjoy it, not without the guilt hangover that inevitably followed. The implication was more than he could handle.

"But you're you now?" he asks, his expression shattered and wrung out. "I thought...I thought I was going to have to kill you for a moment there."

Stiles huffs out a laugh. "Don't sound so disappointed."

"Shut up." Derek's mouth draws into a tight purse. "Just shut the fuck up, okay? I thought you were gone."

"Sometimes, I kind of wish I were." He closes his eyes to escape the interrogation. "It certainly would make life a lot easier."

Derek sighs and braces his arms on the sides of Stiles's head. "Don't be an idiot."

"Seems kind of like hypocritical advice coming from you," he says, eyes still closed.

Derek releases a long breath that tickles Stiles's mouth and his tongue sweeps over his lips to chase the feeling.

"You're not me. You're Stiles - I hope - and people care whether you stick around."

Stiles's eyelids slowly flutter open. "People care whether you stick around, Derek."

Derek exhales hotly through his nose and averts his gaze. "Doubtful."

"Hey!" Stiles says, using his newly freed hand to turn Derek's face back towards his. "I care. Okay? When you left without telling anybody - I cared."

Derek's eyebrow cocks in disbelief, but before he can issue another denial, Stiles leans up and captures his lips with his own.

A surprised noise erupts from the back of Derek's throat and Stiles lurches back and covers his face with his hand.

Stiles wonders if pleading insanity is a viable option for him. He was just possessed by something, so maybe he can convince Derek that it's only the demon inside of him who has a hard on for shape-shifters?

"Sorry. I...have no idea what that was." His face burns pink with embarrassment.

"Your heart didn't - you weren't lying when you said you cared," Derek says, sounding positively broken.

Parting his fingers, Stiles steals a peek at Derek through the gap in his hand and the emotion he sees there makes his heart clench.

"No. It wasn't a lie," he whispers, hand sliding from his face.

Derek grabs the front of his shirt and hauls him from the ground, and for a brief moment, Stiles is positive he's about to be murdered. But before he can eke out an apology, Derek presses their lips together and slides his warm tongue inside of Stiles's mouth.

Stiles always wondered what it might feel like to kiss a man. To kiss Derek, specifically. He had imagined it happening in so many different ways, but never in a million years did he think it would happen like this. It was more disorienting than having his body taken over by a supernatural spirit.

He wraps his arms tightly around Derek's neck and holds on for dear life as he's kissed thoroughly.

The kiss is brief, but long enough that Stiles knows he wants to do it again. Many, many times. Several times in a row. In several different positions.

"I still have the keys to your house..." he says, as their mouths slowly part.

"Yeah. I can feel them digging into my leg." Derek's tone is so dry it could be used as kindling.

What the hell does he expect? Has he looked in a mirror lately?

"Fuck you. Most guys would be flattered."

"Depends on which one of you in there is excited to see me."

Stiles licks his lips and hears Derek's breath hitch in his throat. "Does it really matter?"

"Well..." Derek smiles at him - truly and fully - and the effect is blinding. "I have always wanted to try a threesome."