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Katara has never, ever struggled in a class before.

She’s made it all the way to the fall semester of her senior year at BU with her shiny 4.0 intact, and, sure, her biochemistry program has involved some challenging material, but she’s always redoubled her efforts and come out with an A. She’s proud of her record, and she’s never feared for it. At least, not until now.

Even the first half of Organic Chemistry II wasn’t so bad. It took her more studying than usual—something like re-tripling her efforts—but she secured high marks on the first two exams. Now it is November, her other classes are kicking into high gear, and the Advanced Synthesis unit is kicking her ass.

She lugs her books and binders to the Chemistry building study room, her Monday-Wednesday-Friday habit since August. The TA, Haru, holds office hours those afternoons, and she works with him every chance she gets. Sometimes she can make her way through the assignments without stopping to ask him more than a handful of questions; other times, he helps her through nearly every problem. She has a feeling today is going to be more of the latter, and she dumps her stuff on one of the tables with a sigh. “Haru, I think I’m—”

Haru’s desk is occupied, but not by him. A dark-haired guy with sharp golden eyes and a nasty scar on one side of his face has the chair tipped back onto two legs, his boots crossed on the normally pristine desk.

“You’re not Haru.”

His lips curl into a lazy smirk. “No, I’m not.” His voice is low and deep.

“Who are you?” she demands. “Where’s Haru?”

He answers her questions out of order. “Haru is sick. I’m Zuko. I’m his roommate.”

“And this makes you qualified to TA organic chemistry?” She knows she’s being rude, but every inch of this asshole screams superiority complex, not to mention that she really, really needs help with today’s homework.

His smirk deepens. “It doesn’t, but I did make an A in the class, which was good enough for the electrical engineering PhD program.”

She flushes. “Oh.” Shit, she really is being rude.

“Oh,” he agrees, swinging his feet off the desk and letting the chair bang down. When he stands, she sees he is tall and lanky, wearing tight black jeans and a plaid shirt unbuttoned over his vee-neck. He crosses the room until he is at her table and swings an empty chair around to straddle it. “You must be Katara.”

You must definitely be an asshole, she thinks, eying the cliché Bad Boy pose and shaggy black hair. She tries to breathe through her frustration. “Yes. Nice to meet you.”

He doesn’t return the nicety. “Haru told me about you, said you’d be here for sure.” He taps her textbook. “Well, let’s see it.”

Spreading out her notes and papers, she shows him today’s topic and her progress so far (which is not much progress to speak of). “I’m just not very good at synthesis,” she explains quietly.

Zuko props his chin in one hand and points to her current problem with the other. “This part is right,” he says, “so I know you are good at it. You’re just stuck somewhere in here.” He hms and twists his mouth thoughtfully. “Walk me through your process.”

She does, and he pinpoints her issue immediately. It only takes him a few minutes to explain the concept before it clicks in her brain. Soon she is scribbling reactions as fast as she can write and flying through the assignment. He watches her work closely, eyes roving the pages, and leans in to correct her here and there, but mostly she gets it now.

“Wow,” she says, sagging back in her chair after she checks the last problem. “I think that’s the fastest I’ve ever gotten through the homework.” She breathes a sigh of relief and studies her new savior.

The way he’s sitting, she can’t see the scar on his left side. What she can see of his chiseled face is handsome in a devilish sort of way, if you’re into the bad boy thing, which she’s not. Still, the span of his biceps is visible even through the long-sleeved flannel, and he’s close enough to her that she can feel the heat of him, and it turns out he’s a really good organic chemistry tutor. Maybe she was too harsh when she deemed him a jerk.

“Thank you,” she tells him with a smile. “You’re a really talented teacher.”

He laces his fingers behind his head and tips his chair back, a satisfied smile playing over his face. “I know.”

Nope, he’s definitely an asshole.


By Wednesday, Katara is lost in class again and running low on sleep. She trudges up the stairs to the study room and finds a few other students there already—at least she’s not the only one confused. Any comfort that provides turns cold when she spots Zuko leaning over a guy’s notebook, elbows propped on the desk. She’s so pissed to see him and not Haru that she can’t even appreciate her admittedly nice view of his ass from her place in the doorway.

Ok, maybe she can appreciate it a little bit.

She drops her stuff by a table in the back of the room and collapses into the chair, hand on the bridge of her nose. She’d be happy to see him—she could definitely use another of his brilliantly intuitive explanations—if he wasn’t such a jackass.

Just breathe, Katara, she tells herself. You can deal with one guy’s bad attitude for one more day.

Zuko finishes with the other student and pulls the same move as Monday, crossing the room and dragging over a chair to straddle. Katara barely resists the urge to roll her eyes.

“Kat,” he says, by way of what she guesses is a greeting. “Do people call you Kat?”

She fixes him with a glare. “No.”

His answering smile shows off sharp white teeth. “Great.”


She opens her textbook with a little more force than necessary and stabs at the offending page. “This reaction. It doesn’t make sense.”

He studies it for a moment, then studies her. His gaze is intense, and she feels herself flush under the scrutiny. It’s like he can see right through her skull, right into her brain, and if that’s how he can pinpoint her O-Chem struggles, she’s not sure the vulnerability is worth the trade-off.

After a few more excruciating seconds, he looks back at the page and without preamble walks her through the reaction. Just as before, his explanation clicks, and in no time she has the assignment well underway.

While she is working, the other students call Zuko over, and he spends a few minutes with them intermittently, offering quiet corrections and assistance. Curiously, though, he returns to her desk when he’s done each time, as though he’s checking on her progress. She’s nearing the end of the chapter when he finishes helping another girl and sits back down so close his knee bumps into hers. He doesn’t pull away, leaving the warm press of his leg to make her stomach flip, and she gulps.

She’s really not into the whole early-2000’s emo thing he’s got going on, even with the few modern elements splashed in, like the way he’s twisted his long hair up into a bun today, which coincidently reveals the corded muscle of his neck and shoulder. The punk-rock wannabe thing aside, she can admit that he is handsome, but that sharp striking face is wasted on such a condescending guy.

She chalks up the butterfly feeling to delirious exhaustion and writes out the last problem. When she checks her answer in the back, it’s correct, and she lets the book fall shut with relief.

He arches an eyebrow when she starts packing up. “No thank-you today?” he drawls. “No compliment?”

She ignores him. “Please tell me Haru will be back on Friday.”

“Come on,” he chides. “Haru tells me you’re a nice girl. Tells me nonstop, actually.”

And that’s a problem, because she’s pretty sure Haru has a little crush on her, and this piece of information is more of the same. If it makes him more attentive to her in office hours, she could certainly use the help, but she doesn’t mean to lead him on. Haru is nice, and he’s even her type (if you ignore her fling with Jet, which she does, because that would mean she was into the Bad Boy type, which she isn’t). She’s just so overwhelmed with school right now, so worn out, there’s no way she has time to strike up a relationship. She feels bad. He really is a sweet guy.

“Is he okay?” she asks quietly, ignoring Zuko’s pointed remark.

He relents, gives her a real answer. “Yeah, he’s getting there. He thinks Friday he’ll be ok, maybe Monday.”

She grimaces. “We’ll hope Friday. There’s a test Monday morning.”

His teasing smirk is back. “You mean I’m not good enough to help you study for your test?”

She rolls her eyes and zips up her backpack. “Bye, Zuko.”

“Bye, Kat,” he grins.

Over her shoulder on her way out of the room, she yells, “Don’t call me that!”



When she finds Zuko scrolling through his phone at Haru’s desk on Friday, she nearly bangs her head against the wall. She does at least let her textbook drop loudly onto the table, and Zuko looks up with that feral grin she’s coming to know so well.

“Nice to see you, Kat,” he purrs, rising to cross the room.

She grinds her teeth. “Don’t call me that.”

He swoops in next to her. “Now, now. Shouldn’t you be a little nicer to the person who’s going to help you get your precious A?”

She puts her elbows on the table and her head in her hands. “I think it’s too late for an A,” she mutters bitterly.

He shrugs one shoulder. “You could take it now and get a C. You’ll pass the class one way or the other. It’s not a big deal—only neurotic people care about getting an A every time.”

She glares at him. “Also people who need a 3.7 to keep their scholarship and a 4.0 to have a prayer of getting into med school.”

This deflates him a little. “Oh.”

He doesn’t apologize, but he does spend as much time as he can helping her for the next few hours. It’s not much time—the room is full of students cramming for Monday’s test, and they keep Zuko busy. By the end of office hours, Katara is a lot closer to tears than she is to any kind of organic chemistry enlightenment.

This is it, she thinks. My chances of being a doctor, blown to bits by a class I’d never even use. She puts her head on her desk and listens to the others zipping up their bags and filing out of the room.

Black boots enter her field of vision. “Hey,” Zuko rumbles. “It’s going to be okay.” The kindness in his voice surprises her, and she looks up at him. “Listen, if you want more help—I’ll be up here tomorrow.”

She blinks. “Tomorrow’s Saturday.”

He huffs something like a laugh. “I know.”

Her tired brain pieces together that he is offering to come to campus on a Saturday, when there are no scheduled office hours, just to help her. This does not compute with her understanding of him as an overconfident SOB, and she worries the incongruity will push her right over the edge.

“Thank you,” she tells him earnestly.

The corner of his mouth curls up. “There are those nice-girl manners.”

She drops her head back down.



She heads for the study room bright and early Saturday morning, swinging by the coffee shop on her way. After some hemming and hawing—he’s a jackass, but he’s helping her—she buys him a cup along with her own. She arrives at the Chemistry building a little after 7:30, and Zuko is already there, typing away on his laptop.

“Hey, Kat,” he says absently, eyes on the screen. “Sorry, let me finish this real quick.”

She doesn’t bother to correct the nickname, just sets down the steaming coffee cups and pulls out her books.

“Is this for me?” he asks after a few minutes, indicating the coffee, and she nods. He looks between it and her and murmurs, almost too quiet to hear, “Sweet girl.”

It’s a strange thing to say, and she doesn’t think she was meant to catch it. Even stranger is the jolt it sends through her.

She doesn’t have time to examine that, though, and Zuko is already paging through her textbook. “This is where we left off, right?” he asks.

He spends the next several hours alternating between his computer and her notes, tapping at the keyboard while she ponders a problem and returning to her when she has questions. By lunchtime, she feels so much better than she considers an actual lunch break.

“I’m going to walk over to the student center and get some food,” she tells him, standing up to stretch. “Can I bring you something?”

He’s absorbed in his laptop for the moment, chin in hand. “No, I’m good,” he says through his fingers.

“Let me,” she insists. “As a thank-you for helping me. Please.”

This breaks him away from his computer, and he meets her eyes. A look she can’t decipher flickers across his face. “Well,” he says finally, “since you asked nicely.”

He walks over with her, and she pays for sandwiches for both of them. They eat at a little outside table, and Zuko zips his jacket against the late-November chill. “Aren’t you cold?” he complains.

She smiles. “I’m from the South Pole. This is balmy.”

He considers this. “Ba Sing Se is a long way from the South Pole.”

“Ba Sing Se has the best university in the world,” she counters. “It’s a long way from the Fire Nation, too.” His pale skin and yellow eyes are a dead giveaway.

“I don’t mind the distance.” It’s a cryptic answer, but she doesn’t press. She has a sinking suspicion it has something to do with the angry scar over his left eye and cheek, and she’s not about to pry into whatever awful thing happened to leave such a prominent mark. She knows that modern medical techniques have come a long way in repairing burns, and he doesn’t look so old that the injury could predate the widespread use of skin grafts, even if it happened when he was a kid. Someone didn’t take him to a doctor, or at least not to a very good one, and that is too horrific to contemplate.

She decides to change the subject. “So, electrical engineering. How far along are you in your PhD?”

“Only in my second year. I’ve got a ways to go.” So he’s only a few years older than she is.

“What was your bachelor’s degree in? Is it from here?”

He nods. “I did mechanical engineering, and then I got really interested in electrical grounding systems.”

She tilts her head. “Like, when something gets struck by lightning?”

He grimaces. “Exactly.”

She bypasses the grimace, files it away with scar and distance. “Hey, you must know my brother Sokka! He graduated last year from the mechanical engineering program.”

Zuko stares at her in disbelief. “Sokka is your brother?”

“Yep. He’s back in the South Pole now, but he keeps talking about coming back for an MBA. I hope he does.”

“Sokka,” Zuko repeats. “Man, that guy was a genius. Life of the party, too. I can’t believe you’re his little sister.”

She drops her head back. “Thanks.” Every time she thinks he might have some non-asshole characteristics…

He laughs. “No, sorry, that’s not what I meant.” He has a nice laugh. “He used to talk about you all the time. He had a habit of saying how great you were and then threatening to strangle anyone who went near you.”

Fondness spreads through her. “That does sound like him.” She really does hope he’ll get an MBA, for his sake, and if it means they can live close together again, all the better. The South Pole is a long way away, and her first year so far from home would have been unbearable without him checking in on her constantly.

Zuko’s face slips into his familiar smirk. “And all this time he should’ve been threatening Haru.”

It's her turn to grimace. “I don’t think that’ll be necessary.”

“He’s pretty into you.” Zuko rocks his chair back. She wonders if he’s ever fallen out of one that way.

“He’s nice,” she sighs. “Just not for me. Not right now.”

“Maybe later?” Zuko guesses.

She shrugs. “Maybe. Probably not. There’s not really any spark there, you know? But I don’t want to hurt his feelings.” Why is she telling him all this?

“Haru’s a big boy.” Zuko stands up, as if that’s all there is to say on the matter. “Better get back to it.”

She nods, and they return to their work. Katara gathers that Zuko is writing his dissertation proposal, and he tells her a little about it when she takes study breaks. It sounds interesting, although by the evening he is tugging on his hair in frustration. She feels bad taking his time away from the project, and she almost offers to buy him dinner to make up for it, but that feels too much like a date.

And she just told him she didn’t have time for dates.

And she doesn’t want to date him, anyway.

Finally, they call it a night. Katara feels better about O-Chem than she has all semester, and she beams at Zuko even though she knows it’ll go to his head. “You saved my GPA. Maybe my sanity.”

He shrugs. “Haru will be back Monday—although, please don’t come to office hours after your exam.”

“We covered new material on Friday,” she reminds him.

“Overachiever,” he mutters.

She shoulders her backpack. “Night, Zuko.”

“Night, Kat.”


She spends all day Sunday reviewing for her exam, and studying is breeze now that Zuko has made all the concepts slot neatly into place in her mind. It’s almost strange, doing O-Chem without him; she has to remind herself he’s only been subbing for Haru for a week.

And what a strange week it’s been. She feels lighter, less burdened by the specter of failing chemistry, but some part of her feels heavier, warmth and weight settled low in her belly. When she gets into her twin bed for the night, her fingers creep under the elastic of her panties. She could use the stress relief, she reasons with herself. She lets her mind wander while her hand works, and when her orgasm shudders through her, she swallows back Zuko’s name.