A/N: This story was born after reading all these amazing, fantastic Sterek Soulmates AUs and wanting to be able to write one of my own. It took months after I initially found the trope to come up with my own idea, but I started working on this back in November. Now I've written twelve of the fourteen chapters and I feel comfortable starting to post it, because it's not likely to be abandoned before I finish it. :P Fair warning: This can definitely be categorized as angst with a happy ending, and will be explicit. Updates will be twice a week, on Saturdays and Wednesdays. Happy reading!

It was almost like it was happening in slow-motion. Stiles could see the moment the feet tripped over the loose stone in the path-he'd been telling Finstock for months that they needed to get that damn thing fixed because someone was going to get seriously injured someday-and his eyes flew up instinctively to the coffee cup that was held a little too loosely, apparently. He could almost make out all the letters on the cup as it came flying at him, the lid popping off and a spray of dark brown liquid arcing the short distance between them to splatter all over his old maroon Beacon Hills High t-shirt.

"Oh my God." The voice, presumably belonging to the owner of the coffee that he was now wearing, was horrified. "I'm so, so sorry."

Stiles brushed at the coffee droplets covering the printed letters, grateful the material was slick and he was able to flick most of it away. The spaces in-between the letters, however, were soaked brown. He was ready to make a smart-ass remark when he glanced up and saw the worried face belonging to the owner of the coffee.

He was inhumanly beautiful, and Stiles was lost.

"Uh, don't worry about it," he mumbled, stumbling over his words. "I'm no stranger to coffee stains all over my clothes. Although I'm pretty sure this is the first time that it's actually someone else's fault."

Then the stranger laughed, lips pulling back in an incredible smile that revealed bright white, adorably imperfect teeth, and he went from being inhumanly beautiful to otherworldly. Angelic. Perfect.

"Still, I'd feel better if I made it up to you somehow." The grin was blinding, and Stiles stared at him in stupefied disbelief for a few moments before he realized he was probably expected to say something.

"I can't think of anything," he said stupidly. "I mean, you're the one who lost your coffee."

The gorgeous creature in front of him looked at him shyly. "I definitely need a new one before my Econ class or I'll end up asleep and drooling all over my notes on price theory. Could I get you a cup, too?"

Stiles blinked. He was pretty sure he was hallucinating, because at no point in his life would that perfect of a male specimen ever be interested in spending more time with him than he would otherwise have to. "Uh, sure. Sure," he repeated, mortification creeping in when he realized he was probably looking (and sounding) somewhat like a stoned half-wit. He shifted his book from his right hand to his left and stuck the now-free hand out to shake the stranger's. "I'm Stiles Stilinski."

To his credit, the other man didn't give him a funny look or make the expected joke about his parents' cruelty upon hearing the unusual name. He didn't even ask if it was a nickname the way many people did, often with a look that begged him to say yes. That automatically earned him ten points in Stiles' book. "Derek." The stranger-Derek-gave him a kind of wistful smile that sparked Stiles' curiosity, but then he was returning Stiles' handshake firmly. "Derek Hale."

He stilled, a chill racing up his spine and the back of his neck. The initials tattooed just below his hip bone, his soul mark, seemed to flame against his skin, almost throbbing. It wasn't the first time he'd met someone with the initials DH, of course, but it was the first time he'd had such a powerful reaction to the person. His desire to actually get to know Derek prevented him from being blunt and asking which initials were tattooed on the other man's body. He didn't want to know that they weren't his own.

If Derek noticed Stiles' odd reaction, he was too polite to mention it. Stiles fell into step with the other man as they headed back in the direction Derek had just come from and Stiles had been going to begin with, toward the campus coffee shop. "So you're in Econ, huh?" Stiles asked, trying to come up with a conversation starter. "You with Coach Finstock?"

Derek made a face. "Yeah. I don't know how that man hasn't given himself a heart attack yet."

Laughing, Stiles nodded in agreement. "Scott and I were convinced he'd have a coronary before the end of our senior year."

"Scott?" Derek's voice was both hesitant and slightly hopeful, and Stiles looked at him oddly.

"Yeah, my best friend. We went to high school in Beacon Hills together, and Coach was our Econ teacher there. We started college last year and apparently the man is a glutton for punishment, because he accepted a position teaching Econ here the same semester we started." A bright grin lit up his face. "Either that or we're his favorite students ever and he just couldn't bear to let us go."

Derek returned the grin. "I could see you being his favorite."

Scoffing, Stiles opened his mouth to reply, then ducked behind Derek to avoid the kid that came barreling onto the path in front of him. The kid snatched a rogue Frisbee out of the air and then ran back onto the grass toward his friends, and Stiles resumed his place beside Derek. "You clearly don't know me very well," he responded finally. "The reason Scott and I expected him to have heart issues was because of us. Specifically me."

Derek was quiet for a moment and Stiles chanced turning his head slightly in order to get a glimpse of his expression. He appeared deep in thought, as if he was warring with himself. Eventually one side seemed to win, because Derek glanced over at him and smiled hesitantly. "You're right, I don't know you very well. But maybe we can change that?"

"Sounds good to me," Stiles said agreeably, his heart thumping double-time. This absolutely wasn't happening. He was going to cry if his initials weren't branded somewhere on Derek's body. "So, how long have you been going here?" he asked, striving for casual and not altogether succeeding. "I know I didn't see you around campus last year."

Derek shrugged one shoulder. "I transferred from UC-Sacramento this semester," he replied. "I want to go here for my Master's degree when I finish my undergrad."

"Which is when…?" Stiles prompted.

Derek flashed him another one of his heart-stopping grins. "At the end of the year. I'm a senior."

Stiles sighed mournfully. "I'm just a lowly sophomore," he began, his voice pathetically sad, and Derek chuckled. "Although you wouldn't know it from my course load," he added with a grumble. "I'm taking all junior-senior level courses. My idiot advisor talked me into double majoring. I've decided I'm breaking up with her."

Laughing, Derek shook his head. "And here I am in entry-level Econ," he joked, pushing open the door of the coffee shop and holding it open for Stiles. "You must think I'm pretty stupid."

Stiles cocked his head appraisingly, then grinned. "I only think you're stupid because you're taking it with Coach."

"In my defense, I don't have four years of history with him," Derek protested. "I had no idea what I was setting myself up for when I picked his section."

Stiles threw his arm around Derek's shoulders without even thinking. "Stick with me, young Padawan. I will teach you the ways of UC-Berkeley. The teachers to avoid, the dorms with the best parties, and the who's who of the student directory."

Derek turned his head just enough to look down at Stiles, a shy grin lighting his face. "I already know the most important person here, everyone else is just going to be second best."

Stiles tamped down on the butterflies racing around in his stomach like they were on methamphetamine. Don't get your hopes up, he cautioned himself. You have no idea what initials are branded on his skin. He's probably not even meant for you. Instead of acknowledging Derek's compliment, Stiles scanned the menu board as if he didn't already know exactly what he was going to ask for.

"Welcome to Bean Scene, what can I get for you?" the redhead approaching from behind the counter asked them, blowing out a breath and ruffling the wisps of hair that had fallen to frame her face. She leaned into the counter, bored, and clearly didn't give a rat's ass what they wanted.

Stiles glanced down from the menu board and broke into a huge smile. "Lydia, my love, when did you start working here?" he asked in delight. "As a matter of fact, when did you start working, period?"

She made a face at him and he could see Derek glance between the two of them bemusedly, evidently trying to figure out how they knew each other. "My mom told me she wasn't paying for my credit card this year. She wants me to work to pay it off. It's horrible, Stiles. I was not made for the working world."

"Don't worry too much," Stiles assured her. "You'll find some rich moron you can ensnare in your black widow's web and suck him dry, and then you can quit your job."

She perked up. "Do you really think so?" He nodded. "Aww, you're so sweet. Just for that, your drink is on the house."

Stiles nudged Derek with his elbow. "Guess you'll have to owe me another time."

Derek nodded, pretending seriousness. "I think I can work with that."

Lydia flicked a glance between the two of them. "Is this your newest victim?" she asked sweetly, and Stiles glared in response.

"Derek Hale," Derek supplied, nodding in acknowledgment, and Lydia's eyebrows shot into her hairline as she turned to Stiles with an open mouth.

"His initials," she began, and Stiles waved her off.

"Yeah, yeah. Just get me a double espresso, okay? I have Molecular Neurobiology in a half hour and I'm going to crash hard if I don't have something to get me wired up first."

He caught the dumbfounded expression on Derek's face and winced, waiting for the inevitable comment. Instead, Derek addressed Lydia without taking his eyes off Stiles. "I'll have the same."

Lydia smirked. "Stiles can mainline espresso for days and still be his version of normal. I'm worried what it would do to you, though. You don't strike me as the type to substitute caffeine for oxygen."

"I have Econ with Coach in an hour myself," he replied, and she sighed.

"Understood." Turning slightly, she snagged two cups and scrawled on them, then shoved them at the freshman who had the bad luck of being her on-duty barista, glaring at him to make him move faster.

"Don't I owe you money?" Derek asked, amused, and she sniffed disdainfully.

"I get two free drinks per shift and I don't drink coffee. This is me being generous. Take advantage of it." The barista tentatively set down the two cups in front of her and she pushed them at Stiles carefully. "You two go enjoy your liquid evil. And Stiles? We need to talk later." The look she gave him told him she would not tolerate him trying to avoid her, and he sighed and nodded.

Derek followed Stiles to a pair of low-backed armchairs in the back corner. Stiles dropped his book on the small round table in front of the chairs and plopped down in his, leaning back and inhaling the coffee appreciatively. Derek eased into his seat and glanced over at Lydia before refocusing on Stiles. "She's a little intense."

Stiles chuckled. "That's part of her charm. She's a porcupine on the outside, and a… little less prickly porcupine on the inside."

Derek looked down at his coffee, pretending to examine it, and Stiles waited for him to spit out what he was obviously thinking. "So were you two ever a, uh, thing?"

"Well, I was in love with her from third grade through junior year," Stiles admitted, and Derek deflated a little, and oh God, Stiles was in so much trouble with the way that evident disappointment sent his heart into fluttery overdrive. "But that was about the time I realized I didn't actually like girls romantically, or, y'know. Sexually. I stopped imagining happily-ever-after with her and she became my other best friend. We've pretty much been tighter than Beyonce's booty shorts ever since."

Derek snorted and choked on a sip of his espresso and Stiles had to reach over to whack at his back with one hand, his long, spidery fingers splayed out over the cloth of Derek's shirt, and he could feel the intense heat seeping into his palm. "Thanks," he wheezed when he could breathe again.

"No problem. I'd hate for you to choke and die during our first meeting." The thought, And besides, if you're going to choke around me, it's not going to be on coffee, sprang to mind, and he desperately forced it down before it could find its way to his runaway tongue. "So what's your major?" he asked, rolling his own eyes at the boring, clichéd question, while simultaneously grateful he'd at least come up with something to change the topic.

He rubbed at the back of his neck, looking a little sheepish. "Civil Engineering. When I graduate I'll be going into City and Regional Planning."

Stiles blinked. "Impressive, dude. What inspired that?"

Derek's tight smile made it clear that it wasn't a subject he felt comfortable discussing. "It's expected of me. Carrying on the family tradition."

Gears were whirring in his head and all of a sudden something clicked. "Oh my God. Derek Hale. Talia Hale's son?"

The tight smile became brittle and looked as if would shatter if Derek put any more pressure behind it. "Yes."

Stiles nodded. "Cool. Um, just so you know, I aced all of Coach's Econ classes." He gave a tentative, lopsided grin. "If you need tutoring help, my nights off are Wednesdays and Thursdays."

Beautifully long, thick lashes blinked at him in suspicion and disbelief. "I admit I'm Talia Hale's son and you tell me you're available for tutoring?"

Shrugging, Stiles kicked back another swallow of espresso, feeling the caffeine start to buzz in his blood. "If you wanted to talk about your family you would. You obviously don't. Ergo, change of subject."

Amusement played at the corners of his lips. "Ergo, huh?"

"It's a lofty word. I'm a lofty kind of dude." He grinned cheekily, a thrill blooming in his chest at Derek's hearty laugh. "I really hate to do this, but I have fifteen minutes until class starts and it's a ten minute walk across campus." He leaned forward, snagging Derek's cup and carrying it to the counter so he could grab a pen. When he walked back over to where Derek was still sitting and watching him with a fond smirk, he presented the cup, which now bore his phone number. "If you're interested in tutoring. Or just hanging out."

Derek took the cup, studying it for a moment. "Is there anything else in that offer?" His eyes stayed on the cup, not brave enough to meet Stiles', and Stiles swallowed. He hated this part. He didn't want to waste his time with someone he didn't have a future with, but he didn't want to have the soulmates talk with someone he barely knew. It was awkward. Not for the first time, he resented the ambiguity of the soul mark. You sort of knew, but you didn't really, not right away.

"There's a conversation we'll need to have before I can give you an answer to that," he replied carefully, and Derek's face fell, almost imperceptibly, but Stiles was watching him closely and he caught it. "Let's start with friends, okay? I like you. I want to spend more time with you. Whether it's of a romantic nature or not… We can figure that out later."

Derek smiled ruefully. "I can live with that," he allowed. He reached out for Stiles' cup while reaching a hand into his backpack and pulling out a Sharpie. After he'd scrawled his number on it and returned the cup, he made a shooing motion with his hands. "Don't be late for class. I'll talk to you later." He flashed a warm grin at Stiles before leaning down to pull his Econ text out of his backpack, seemingly easily dismissing Stiles.

His confidence was the sort that confounded Stiles. He'd been direct and open from the moment they met, but his obvious shyness had popped up unexpectedly, leaving Stiles to wonder if he was of the "fake it 'til you make it" school of thought. Either that or he was the kind of guy who'd spent his entire life being told he was amazing and gaining confidence because of it, but underneath it all he wondered if he really was everything he was made out to be.

Considering his mother's family had pretty much created the town of Beacon Hills from the ground up, the second option was probably a safe bet. Talia Hale was third-generation mayor of Stiles' hometown, and he imagined that if Laura wasn't the eldest Hale child, Derek would have been fourth generation. He might still, if the rumors about Laura wanting to go into fashion were true.

Stiles still couldn't wrap his mind around the fact that the kid that he'd last seen when he was a skinny, awkward ten-year-old with so much hair you could hardly see his eyes through it all, was now quite literally the most gorgeous man he'd ever met in his life. He still remembered the picture of Derek with his family in the local paper, about two weeks before they shipped him back off to Sacramento where he lived with his Uncle Peter. Derek had been standing there sullenly and peering out from underneath his mop of uncontrollable hair that Talia had clearly tried, and failed, to tame. Even at the tender age of seven, Stiles had pitied the kid because he was so homely.

Twelve years later Stiles was laughing at himself for how wrong he'd been, and marveling at how kind the years had been to Derek. He had totally Longbottomed, and damn if that didn't bring other, dirtier, images to mind.

As he made his way across campus, sliding into his seat in his Neurobiology class with seconds to spare, he found himself fervently hoping for about the dozenth time in the last hour that when he and Derek finally had that soul mark talk, he would discover that his initials were somewhere on Derek's body. And they would live happily ever after.