"Actually, it isn't," Stiles says miserably. He's hanging from the bed, upside down, his feet up on the mattress and his head in Allison's lap, staring at the ceiling as she cards soothing fingers through his hair. God, he loves Allison, Allison is awesome. Scott is so, so lucky. Much luckier than Stiles will ever be. "I checked the campus policy, there are no official rules about consenting adults having a relationship, even though it's unanimously frowned upon."

"Since when do you care if something's frowned upon?" Lydia asks, flicking her hair over her shoulder. "You once went into the woods to find a dead body, for no other reason than thinking it would be fun. I say go for it."

"Right. I'll just go up to him and ask him if he wants to go on a date and maybe also spend the rest of his life with me," Stiles snarks. "'Cause that'll go over so well."

"Hold on, you wanna spend the rest of your life with him?" Scott gapes at him and hits his shins with a pillow. "Stiles, you didn't tell me you were in this deep!"

"'s not like it matters," Stiles mumbles. "I'm just one face in a lecture room with sixty students, he barely even knows I exist."

Lydia snorts. "Oh, trust me, honey, he's noticed you."

Stiles accepts the bottle of rum going around and takes a sip. He spills some on his shirt, because that's just his fucking life, and also, drinking when hanging upside own is harder than one would think. Especially when you're already pleasantly buzzed. "The only reason he notices me is because Brad keeps talking to me in class until professor Hale glowers him into silence. The only thing I am to him is an annoying student who doesn't pay enough attention during his lecture. Pretty sure that makes him dislike me, not feel the irresistible urge to jump my bones."

"So, what about that Brad guy?" Kira asks. "I'm not saying you should settle for the second best, but he seems like a nice guy, right?"

"Yeah, he always shares his notes with me when he sees I've been too busy daydreaming about professor Hale's everything to follow the lecture. Not that I need them, because Lydia's notes are a billion times better, but, you know. 's nice."

"So he's definitely interested," Kira concludes.

"He probably thinks you're thinking about him," Isaac smirks. "Poor guy. If only he knew you had a raging hard-on for your teacher."

"Do you like him?" Allison asks.

Stiles blinks up at her. "Who, professor Hale?"

She rolls her eyes. "No, dummy. Brad. It sounds like he's seriously working up the courage to ask you out, and I think you should think about what you're gonna say, how you're going to react. Are you going to turn him down if he asks just because you're in lust with someone you've already said you won't go after, or are you going to give him a chance?"

"Dunno," Stiles says slowly, shrugs. "He's nice. And pretty. Not as pretty as professor Hale, though. And when he talks about numbers, he doesn't sound like he's talking about sex."

"Christ," Jackson murmurs. "Go for it. You seriously need to get laid. Now someone pass me the booze, I'm not nearly drunk enough for this."

"I don't even like you a little bit," Stiles informs him solemnly, but passes him the bottle anyway.

∞

"Hey, how was your weekend?"

Derek feels his eye twitch in aggravation when he sees Brad Thompson sliding into the seat next to Stiles and immediately starting to chat him up. Stiles smiles at him and Derek forces himself to focus his concentration on the papers on his desk to make sure his notes for the lecture are in the right order, unlike last time when he got horribly distracted by Stiles chewing on a pen. Or the time before that, when it was Stiles gnawing on his lower lip that almost had him miss a question one of his other students asked.

It's been happening a lot, this semester. Derek is pretty sure he's never screwed up his lectures as much as this term. In fact, he's never once screwed up at all. This year, his concentration has gone to shit; he's always paying more attention to Stiles than to what actually leaves his mouth.

The dean should probably fire him.

It's just...it's freaking impossible to not notice Stiles. He doesn't demand attention the way Lydia Martin does, striding into the room with her head held high like she owns the place and a confidence and intelligence that baffles Derek and a look that dares everyone to not take her seriously and suffer the consequences.

Stiles got Derek's attention because he is always in motion. Tapping his fingers, wriggling his leg, running a hand through his hair, clicking his pen, licking his lips. It used to irritate Derek like nothing else; until he realised he wasn't the only one who had noticed that Stiles wasn't only beautiful and aggravating but also incredibly smart and funny. Derek hasn't been able to keep track of the number of times he's had to yell at Thompson and him to shut up. And no matter what Laura and Cora say, he's not stricter with them because he's jealous because Stiles is generally paying more attention to Brad than to Derek's lecture.

He's not.

He's still going to have to come up with a plan to get back at his sister for mocking him that he shouldn't be surprised, that a dead fish would be more interesting than his classes.

Stiles and Brad begin chatting animatedly, and Derek tries to squelch the sudden wave of jealousy  and tune them out. There's still five minutes left until the class starts, so he can't really tell them to shut up just yet, but he doesn't want to listen in. Brad's awkward attempts at wooing Stiles with lecture notes aren't something he can deal with first thing Monday morning, and he really, really doesn't want to know if Stiles finds Brad's flirting adorable. Personally, Derek thinks it's ridiculous. He could do it ten times better - and God, he's going to burn in hell for fantasising about a sophomore.

As it turns out, it's basically impossible to not overhear their conversation considering they're sitting in the front row. He tries, okay, he really, truly tries, but then Brad pops the question and well, his voice isn't low enough for him to not hear it. That's the only reason Derek listens in, because he can't help it, not because it has become a habit to focus on anything Stiles says, or because he silently prays Stiles will shoot Brad down.

He glances at Stiles, who looks flattered but hesitant. Derek swears his eyes dart over to him and then back again, but that's probably only because Stiles wants to make sure his teacher doesn't learn about his private life. He gets it, he wouldn't have wanted his professors to know about his love life, either. Who even asks someone on a date in class? Why wouldn't they wait to have that conversation in private?

Stiles takes a deep breath. "Tell you what," he says decisively. "Let's make a deal: I'll go on a date with you if you manage to ask professor Hale one question he cannot answer correctly."

Brad blinks at him. "That's a weird deal. But okay."

"Hey, teach," Stiles calls, and Derek wants to die a little for being drawn into this. "Brad here would like to ask you a question."

"It's professor Hale," Derek reprimands him and turns to Brad. He shouldn't get involved. He shouldn't. Especially if the temptation is very big to effectively cockblock Stiles by making sure his answer is one hundred percent correct. "What's your question?" he asks, trying to stay polite. Knowing Brad, it probably won't be about the class; Brad isn't the weakest student in his class, making up for a lot of understanding he's lacking by the sheer amount of studying he does, but there's no way he can ask a question about economics that Derek can't answer.

Damn, what if he asks a trivia question about Star Trek, or another topic that Derek knows nothing about?

Brad thinks about it a moment longer, then grins like a Cheshire cat. "Will he go out with me tonight?" he asks, gesturing at Stiles.

Derek's eyebrows shoot up. Clearly, he thinks he's being clever. "No," he says, looking at Stiles. "He won't."

Stiles is still gaping at him when he turns his back and stalks back to the desk to start his lecture. He hears Brad crowing in glee, saying that was clearly the wrong answer and asking when and where to pick Stiles up, and Stiles answering distractedly that he'll tell him later.

He barely makes it through the lecture, constantly feeling Stiles' inquisitive eyes on him.

After, Stiles is taking his time packing his stuff away, lingering awkwardly between the rows of seats long after Brad had to rush off to his next class. He waits while Derek answers one student's questions about the formatting of the upcoming paper, even though he explained that in detail in the syllabus, Jesus fucking Christ, and tells another that no, going on a weekend trip to the Bahamas is not a fucking valid reason to ask for an extension and he'll have to hand the paper in next week just like the others. It's only when they have trotted off and he and Stiles are the only ones left in the room that Stiles sidles up to him and clears his throat.

"So," he begins haltingly and licks his lips. Derek tries, and fails, not to follow the movement with his eyes. "You seemed pretty sure of your answer earlier. About me not going out with Brad tonight."

"Yes."

"Okay." Stiles frowns. "What made you so certain that would be the answer?"

There's a myriad of reasons Derek could come up with, all of which don't even need to reveal his pathetic crush on his student. But the look Stiles gives him is cautiously hopeful, and Derek thinks fuck it, the semester ends in two weeks anyway, and then he won't be Stiles' teacher anymore.

"Because," he says, picking up his books and straightening his back, "you're having dinner with me tonight."