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Sokka knows he’s lost it when a skeleton shows up in his dreams.
In his defense, he’s been up since six, having to settle a roommate dispute involving a set of Ikea plasticware and a cat that had somehow been smuggled into the decidedly animal-free dorms of BSSU—and Sokka’s exhausted, between petty RA disputes and barely surviving his TA office hours for gen chem.
(He swears some of the freshmen are smarter than he is. One of them was asking him about godsdamn crosslinking polymers, for fuck’s sake. They haven’t even finished ideal gases yet. Sokka’s not even sure he remembers what the ideal gas law is. Something with the word NRT in it? And the promise that the equation wouldn’t blow up in his face.)
Point is, Sokka’s on the couch halfheartedly reading over a messily-written pset when his mind decides to wander, manifesting himself into a desolate room in his mind, the ruined backdrop straight out of the lecture hall in the back of the life sciences building at BSSU. The blackboards are dusty, covered in layers of crusty-chalk, drawings of fingers, lungs, nerves snaking down the sides.
Just the sight of the blackboard is enough to make Sokka’s skin crawl—but it’s the skeleton manifesting in the corner of the lectern and the giant letters on the topmost blackboard that make his sus sensors go on high alert.
ANATOMY.
(Yikes.)
Even the word anatomy triggers Sokka’s fight-or-flight instincts, dredging up fond memories from the first time he attempted to take the class and completely flunked the first exam. “The average for the exam was a 74%, with a high of 94% and a low of 23%,” the professor, a wizened old woman by the name of Lo, had announced, scratching the numbers on the blackboard.
What idiot would get a 23% on anatomy? Sokka had snickered to himself.
(That’s right. He did.)
Sokka had ended up withdrawing from the class, sure that he would never have to see another cadaver again, but fate has a really funny way of reminding you how much you suck at something. Like when he realizes how many grad biomed engineering programs require anatomy, or at least some form of experience demonstrating that yes, he knows what the human body looks like and is remotely qualified to poke around the biotech sphere, thank you very much.
It makes sense, especially since Sokka wants to go into advanced prosthetics or artificial limbs. If he can’t figure out how bones fit together, how is he going to be able to make fake bones for real people in the first place? He sure as hell won’t be making an arm for a patient who needs a foot, of course.
But truly, when it comes to anatomy, though, that’s where Sokka truly meets his match. His kryptonite, as Suki calls it, except Sokka isn’t an alien with superpowers, and his weakness is literally a pile of calcified cartilage arranged artfully into some semblance of da Vinci’s Vitruvian Man.
Anatomy just doesn’t make sense to him at all.
Physiology—now that’s something he can get behind, all systems and machinations and minute details about how different organs work together to maintain homeostasis. Sokka likes that, likes how he can visualize the individual paths of the circulatory system, how it interacts with the lymphatics, how everything gets muddled in the portal systems before eventually straightening itself out.
He’s always been more of a systems guy, taking things apart to see what happens, tinkering with broken microwaves and Katara’s old MP3 player and Gran-Gran’s old pacemaker. (Mom hadn’t been exactly thrilled with all of his experiments, but Dad had supported him with all the enthusiasm a befuddled father could give.) He likes to pick apart the details, figure out which parts work with which, the lynchpin that holds complicated machinery together.
It’s honestly laughable, how a class like anatomy could be the one thing holding Sokka back. He’s conquered the absolute maze of mammalian cell signalling systems, survived the hellhole of organic chemistry lecture and lab with barely a scratch, even catapulted his way through baby physics and made it through to the other side, until until one thing stood between him and that coveted piece of cardstock.
The fucking bones class.
Bones are just the worst. Yeah, Sokka knows that anatomy isn’t just bones, but it really feels like it most of the time. Bones just make no sense to him at all. In his opinion, they’re weird and spongy and kinda-living-but-not-really, but that argument isn’t enough to garner a passing grade from Professor Jian. The man practically rules over the anatomy lab with a fibrocartilage fist, making Sokka’s life a living hell since day one. It’s just dumb luck that the only anatomy offered in the spring is clinical anatomy, so he’s been stuck with a bunch of clicker-happy premeds clawing over each other to get a recommendation letter from the professor and a handful of gen bio majors who were just looking for an elective but accidentally ended up choosing the wrong class.
(Oh, and there’s this one weird kid who’s really into forensics or something. Sokka doesn’t remember his name—he’s only talked to him once—but he’s spent an entire lecture watching the guy chew his way through two ballpoint pens while Professor Jian lectured about the importance of the brachial plexus. Not that Sokka blames the guy. Nerves make him nervous, too.)
Sokka doesn’t understand why everyone is so up in their ass about anatomy. He’s just here to figure out where everything is in the body, not to watch the premeds fight for the closest spots next to the professor during dissections. He doesn’t actually care about peeling apart the individual layers of the spinal cord or slicing through a heart. All he wants to do is to pass this class so he can actually: (1) graduate, and (2) show grad school programs that yes, he knows the difference between perineurium and perineum.
(And before you ask, yes. There’s a huge difference. Just ask the girl from—
Wait. No. Don’t ask her. Sokka’s never gonna live it down.)
Fuck, how long has it been since he’s dreamed about a fucking class? Sure, there’s the midterm next week—
Wait.
Hold up.
Midterm?
Fuck.
Apparently the mere thought of a fucking anatomy exam is enough to send Sokka into anaphylactic shock, every mast cell in his immune system rioting against the mere thought that, gods forbid, he actually has to apply knowledge in this particular class.
Frick frack the crick crack.
It shouldn’t be this hard—really, it shouldn’t—but Sokka’s brain is completely and utterly exhausted at this point, like freshly-washed laundry being wrung out to dry on the clothesline: no new info in, old info slowly dripping out. In hindsight, taking anatomy earlier when he had the brain space to memorize bony features would’ve been the smarter way out, but it’s really too late for that now. Sokka’s sure he’ll end up spending most of his weekend wandering around in a hazy stupor of bones and moans, waiting, just waiting for the rest of the semester to obliterate him.
He’ll just have to pull out the big guns, then. Maybe sleep with Netter’s Anatomy Coloring Book under his pillow at night and passively absorb knowledge through osmosis. Maybe pull another all-nighter right before the actual exam. Maybe offer up a few extra prayers to the ones above. Please. All I wanna do is pass. Just let me have this small victory, alright?
And if Sokka does well on this exam, then he’ll go out to get himself something to celebrate. He’s partial towards Wendy’s Four for Four, although he’s down for something a little more. A burger and some fries? Definitely extra fries, no ketchup. Or a milkshake? No, and a milkshake. The boozy kind with extra toppings and an Everest of whipped cream with a cherry on top that tempts diabetes and sends Zuko into tachycardic shock, because no way in hell is that good for you, gods, Sokka, what the actual fuck? but Sokka’s gonna drink it anyways, partially because it’s so damn good but also just to spite his boyfriend for shits and giggles.
A noise startles him out of his thoughts. The skeleton is waving a laser pointer now—gods knows where it found one—and pointing at a radiograph projected on the blackboard.
“What is the name of the bony feature as indicated on the structure?” a voice that sounds suspiciously like Professor Jian booms from the lectern. Sokka swears it didn’t come from the skeleton (skeletons don’t even have the vocal cords to vocalize, alright?), but it makes no difference. He watches as an arrow appears on the radiograph—the radiograph that’s straight out of Sokka’s repressed memories of anatomical identification. It’s the worst part of the exam, far shittier than the conceptual questions which are actually surprisingly bearable.
Sokka squints at the radiograph.
Unlabelled? Check.
Pixelated to hell and back? Check.
Randomly placed arrow with no indication if it’s pointing at or located in the structure of interest? Triple check.
“You have thirty seconds,” the voice intones, and an invisible clock begins to tick.
The pin drops.
“Uh. Uh. Uh,” Sokka stalls.
Gods. He can barely read the fucking radiograph, let alone identify what fucking part of the body this was. Okay. He can see a bend. Looks like some kind of joint? But what kind of joint? It doesn’t look like the chest, or the head, or the back. Maybe arm? But what part of the arm? Or it could be the leg? It could totally be the leg—
“Ten seconds.”
“I haven’t even—” Okay. Just go with the arm. You don’t have time.
“Nine—”
“Radius?” Sokka wracks his brain for more words. “Ulna? Humerus?”
Those are bones, right? But the question was specifically about bony features—oh, the fucking bony features—fuck, Sokka still doesn’t know the difference between a tuberosity and a tubercle, only that both of them have the word tuber- in it, which makes him think of potatoes, which reminds him of Arby’s curly fries—Arby’s: we have the meats—he could really go for a Meat Mountain right now—
“Four—”
“Tubercle?” Sokka squawks.
Wait a sec. The arrow is pointing at one of those joint junction things for bones, so it’s probably some sort of, what’s the word for it—sounds like corona or something—corona process? No, that can’t be right.
“One—”
“Corona process,” Sokka offers meekly, even though he’s willing to bet his entire corporeal being that this particular bony feature doesn’t exist. Corona’s a beer, for one, and Sokka’s pretty sure he’d remember if anything in anatomy was even remotely related to alcohol.
“Incorrect. The correct response was: olecranon.”
Oh.
Well.
The sting of Sokka’s wrong answer quickly fades. He’s so used to being corrected by Professor Jian in class—and in front of the gossipy premeds, no less—he’s stopped internalizing his mistakes.
Unfortunately, the skeleton at the lectern seems to have other ideas. Sokka watches as it jerks to life, bones creaking into anatomical position as the skull tilts at a grotesque angle. The skeleton takes one step forward, then another, teeth clattering and bones rattling before the entire thing disappears into a haze of dust, with only the skull remaining as it falls to the floor, still grinning menacingly in his direction.
Sokka gulps.
“—kka.”
Sokka walks to the lectern, bending down to pick up the skull in his hands.
“—kka.”
Sokka shakes his head. The skull is frowning up at him now—can skulls even frown?—teeth held in place by bones he can’t even remember. Something-something-mandible? Aren’t ants the ones with mandibles?
“—kka.”
“Wha—?” Sokka’s still staring at the skull in his hands, like Hamlet murmuring to Yorick’s head. He traces over the sutures—coronal, sagittal, lambdoid, squamosal—ooh, squamosal like squishy—
“Sokka. Wake up.”
The skull dissolves into a pile of dust as he jolts awake, eyes crazed, chin wet, hands fumbling for the nearest weapon he can reach. “Who—?”
Except there’s no weapon, and the only thing Sokka manages to grab is a Sharpie and a fistful of cotton that smells like Tide and oranges and incense. There’s something warm and firm under his head, and Sokka looks around wildly, a coffee table to his right and a solid wall of gray to his left.
Something flicks against his forehead.
“Ow!”
“It’s me, sleepyhead.”
Huh? Is that—?
“Babe?” Sokka looks up. A smile tickles his lips, something warm in his cheeks when he meets his boyfriend’s gaze.
“Morning, sunshine.” Zuko stares down at him, a scowl across his pretty face, hair tied in a messy bun. He’s holding a half-peeled clementine in one hand, the spiral peel dangling over Sokka’s face and hovering right above the tip of his nose.
The pillow under Sokka’s head shifts, and Zuko winces slightly.
“Pretty sure my legs are asleep,” he says nonchalantly, and Sokka belatedly realizes that he’s just taken a fat nap in his boyfriend’s lap.
“Oh, gods, I—”
“It’s fine.” Zuko continues peeling the clementine. “You looked exhausted. How much sleep have you been getting?”
“Uh—I—uh—”
“You didn’t sleep last night, did you.” Zuko tosses the peel out of Sokka’s line of sight before pulling the segments apart and pressing one to Sokka’s lips. “C’mon. Open up.”
Sour-sweetness explodes in Sokka’s mouth, and his lips pucker.
“Go take a break,” Zuko says as he eats a clementine segment himself.
“Breaks are for wimps.” Sokka’s not a wimp.
“Mhm. Only wimps would say that.”
Sokka huffs. “Not my fault bones are a bitch and a half to study for.”
“But bones aren’t that hard?” The way Zuko says it makes it sound like a question, a lilting tone at the end. “Just memorize the things and you’re good.”
“Easy for you to say, Mister I-Got-Into-My-First-Choice-Med-School,” Sokka grumbles. “Besides. Who said they weren’t gonna tutor me, huh?”
“I have absolutely no idea.” Zuko blinks.
“I—” Sokka flops dramatically around Zuko’s lap in a motion reminiscent of a dying fish. “Zukoooo. Don’t do this to me.”
“Sorry.” Zuko doesn’t sound sorry at all. “By the way. You got a bit of… something on your face, y’know.”
Sokka reaches towards his face, feeling the familiar dampness of post-nap drool on the side of his mouth.
“Oh, shit.” He blindly reaches out for something to wipe his face with. “Did I—”
“Thankfully, no.” Zuko hands him a tissue. “Just your cheek. And your chin.”
Sokka wipes his face gingerly with the sleeve of his hoodie, basking in the eternal mortification of drooling. Gods. Only babies do that. And old people, like Gran-Gran. He’s not Gran-Gran. At least he still has several years before he makes it to the actual drooly age. Sokka’s sorely tempted to dig himself into a hole now, and fuck, isn’t it embarrassing to wake up in a pile of your own drool with your boyfriend staring at you like you’ve grown an extra eye on your head?
(Sorry, cephalic region. That’s one of the words on Professor Jian’s word list for their final. Gotta remember that for the exam.)
(And don’t confuse it with cranial, which only refers to the skull itself, apparently. The semantics of anatomy are more confusing than memorizing SAT-level vocabulary.)
“Gods, how long was I out?”
“An hour?” Zuko looks down at him. “You talked a lot, though.”
“Oh, fuck.” Sokka wants to turtle himself into his shirt in embarrassment.
“Don’t worry. It wasn’t that bad,” Zuko says reassuringly. “I mean, one minute you were mumbling about Wendy’s Four for Four, then something about milkshakes—”
He narrows his eyes. “Don’t tell me you were thinking about those ridiculously caloric boozy shakes from Bumi’s—”
“No, nothing like that,” Sokka cuts in. He sadly yeets the thoughts of Bumi’s Baileys-and-Reese's Peanut Butter Deluxe Oreo Shake out of his head. “What else did I say?”
“—and something about, and I quote—” Zuko curls his fingers into air quotes, “—no, no, no, not the fucking olecranon—”
“But it wasn’t the fucking olecranon! I swear to La, I’m, like, one hundred percent sure it was the, the—uh, the—”
Zuko stares at him.
“—uh,” Sokka says eloquently, because all of his language comprehension has suddenly taken a nosedive into the negatives, “—starts with a C—”
“Condyle?”
“No, not a condyle. Definitely not a condyle. But it was near the elbow—”
“Are you sure it wasn’t the condyle?”
“I—I—” Sokka’s mouth flops open. “I—honest to La, I have no fucking clue—it’s the other thing that starts with a C—uh,” he scratches his head, unable to get condyle out of his head, dammit—condyle sounds like condor, and now he’s wondering if he’s found a new mnemonic about big birds or if he’s damned himself to thinking about condyles for eternity—
“Epicondyle?”
“Will you stop it with the condor—I mean, condyles?”
Zuko hesitates, forehead furrowing. It’s the same look Sokka’s seen a hundred times, especially during MCAT review month and finals season, that look of pure, feral concentration as his boyfriend methodically goes through his mind to extract the correct information. At least, that’s how Sokka likes to think about it. Zuko’s wicked good at memorization, although he doesn’t remember pathways or processes quite like Sokka does. His brain takes to memorization like a desiccated sponge in water, absorbing everything and retaining it with horrifyingly accurate precision.
(Google says it’s eidetic memory. Sokka just calls it black magic.)
A minute passes, Zuko still squinting off into the distance. Sokka looks up at the ceiling, counts the ridges he sees textured over eggshell white. He almost jumps when Zuko suddenly refocuses his gaze downwards, amber striking sapphire.
Zuko scratches his head. “Coronoid process?”
“Paranoid process?” Sokka can’t help but ask.
(Good job. Now you’ve got another fucking mnemonic to keep track of.)
“Uh, no?” Zuko frowns. “I said coronoid process.”
“What the fuck.”
“It’s used to prevent elbow hyperflexion.”
“Can you even hyperflex your elbow?” Sokka tries with his own arm and winces in pain. Apparently elbows aren’t meant to bend in fun or interesting shapes.
“I don’t think so.” Zuko looks down. “—and you just tried to hyperflex your elbow, didn’t you.”
“No?” Sokka rubs his elbow grumpily, a frown on his face as the pinpricks in his arm feed his central nervous system and slowly stimulate his brain. He’s still thinking about the skeleton in the dream creaking towards him, jaw open, empty eye sockets boring into his soul. Gods. Now that’s something he won’t get out of his head for the next few days. Sokka gives himself exactly one-minute-and-forty-one seconds to internally scream before he takes a breath and tries to wriggle off of Zuko’s lap.
“Sokka?”
“I need to study,” Sokka protests, only for Zuko to push him back down.
“No, you don’t.”
“But babe—”
“Shh. Take a break, ‘kay?” Before Sokka can protest, Zuko feeds him another clementine segment. “And hold off on the coffee. How many cups did you have today?”
“Today? Uh—” Sokka pretends to count on his fingers. Truthfully, he has no idea how many cups of coffee he’s consumed in the last few hours, but he’d give himself a generous estimate of… definitely less than ten? Because the last time he ingested that much caffeine, Suki had to bike eight miles to campus at three in the morning to pry him off of the wall of the engineering quad.
(It had been pretty cool, actually. He had made it up two stories before gravity had struck a deal with his ego and nearly sent him plummeting to the ground.)
“Sokka?”
“—not sure?” Sokka offers up his best smile.
It’s clearly not enough, if Zuko’s glare is anything to go by. Actually, it’s more like a look of disappointment, the kind that cuts straight into Sokka’s heart and manifests into a wiggly sort of feeling in his stomach. He hates it when Zuko gives him that face, like Sokka just kicked a puppy or something and now he’s the shittiest person in the world.
“You can’t keep doing this to yourself.” Zuko shakes his head. “Go to bed. Get some sleep, please.”
“Nuh uh.” Sokka finishes wiping off the embarrassment from his face. “I need to study. I have a midterm next week.”
“All the studying in the world won’t help you if you're too tired to function,” Zuko replies. “Speaking from personal experience.”
“Babe, you never sleep.”
“Hrm.”
“Don’t hrm me.”
Zuko doesn’t say anything, only reaches through Sokka’s line of vision—probably grabbing something—but that’s not what catches Sokka’s caffeine-addled attention.
He squints up at Zuko’s arm.
It’s a nice arm, sun-kissed and tanned from their recent trip to the beach, the slightest hint of sinewy muscle joining elbow to wrist, a loop of emerald-gold thread braided in a homemade bracelet threaded loosely around it all. Zuko has nice hands, long, graceful fingers, a scattering of lines criss-crossing across his palm that reminds Sokka of the neural network diagrams he looked at in his machine learning class. A network of veins snake up the side of his wrist and across his forearm, and Sokka follows the path in his mind until it disappears around the bend of Zuko’s elbow.
That’s when it hits him.
Sokka can’t help himself—it’s like taking a kid into a room full of blinking lights and buttons and telling them not to touch anything. You can’t just tell him not to do something and expect him not to do it. It’s all part of the buy-one-get-one-free deal of spontaneity and impulsivity.
And before he knows it, he’s already uncapping the Sharpie in his hand, the cap rolling away as he reaches up and starts to write.
Zuko freezes up.
The clementine peel falls to the floor.
“Sokka, what the f—?”
It’s not the best angle Sokka’s worked with, and he’s definitely no backbreaking Michelangelo painting the Sistine Chapel, but he manages the best he can, one shoulder braced against the side of Zuko’s hip, the other wobbling as he finishes his work and tosses the Sharpie on the coffee table.
CLAVICLE, the letters scream back at him in stark black, bold and foreboding against Zuko’s skin. It’s beautiful, even in Sokka’s questionably shitty handwriting, and the more he stares at it, the more his brain starts to fire. He can feel his nerves synapsing, the connections of smooth-skin-clavicle-anatomy-position-clavicle-collarbone-clavicle-lateral-to-sternum-clavicle slowly clicking into place like a one-thousand-piece Ravensburger jigsaw puzzle.
Ah.
Fuck yeah.
A sleep-deprived Sokka giggles to himself. Why hasn’t he thought about this study strategy before? The cadavers in the lab have nothing on a living, breathing human body. If he just writes all the words down on a diagram—wait, no, a body—if he just writes it all down and studies it carefully, maybe he’ll finally start to memorize where and what everything is. It’s like studying systems, where he can connect everything to each other besides studying each term one by one. Maybe, if he approaches this studying like a system, it’ll become a system he’ll understand.
He’s so pleased with himself, he doesn’t even notice Zuko slowly thawing, only startling when CLAVICLE slowly retreats out of his vision as Zuko brings up his arm and stares silently at the letters decorating his arm.
Oh. Shit.
Because Sokka, in his infinite wisdom and spur of the moment, has failed to consider his boyfriend’s potential reaction to his impromptu art project. Zuko’s completely silent, his entire face impassive except for the tiniest of twitches in his right eye, like he’s on the verge of a complete and total conniption.
“That’s—”
Sokka can’t breathe.
“That’s—”
Aight, I’m fucked.
“That’s—not even in the right place,” Zuko growls.
“Huh?”
Zuko looks like he’s two blinks away from internally combusting. “The clavicle. You wrote it on my forearm.”
“Wait, hold on—what?”
“You wrote clavicle on my fucking forearm.”
“Hold up,” Sokka cuts in, thoroughly confused. “I thought you’d be—”
“Pissed?” Zuko cuts in. “Yeah, I am. Especially ‘cause you wrote this in Sharpie. Going to be an absolute bitch to wash out.”
Sokka cowers. “I’m sorry.”
In all of the two years that they’ve been together, he’s never seen Zuko actually erupt over anything. Sure, there’s the occasional argument, the periodic snarking session when pre-finals tensions are running high, but it’s generally been smooth sailing with a small bump here and there. As impulsive and hot-headed as Zuko might be, he doesn’t usually freak out over anything—usually being the operative word. Sokka finds himself in a pretty precarious position, head still nestled in Zuko’s lap, vulnerable for the snapping. He’s pretty sure his boyfriend knows at least twenty different ways to incapacitate or decapitate him, depending on today’s mood and the exact angle of the sun in the sky.
“But not as pissed as I am about where you wrote it.”
“Huh?”
“Sokka, here’s a tip for you.” Zuko reaches behind his head, and Sokka watches with bated breath when he pulls out a slender highlighter, his hair falling from its makeshift bun and cascading in waves around his shoulders. “You need to improve on your practical identification.”
He holds up a slender highlighter, fluorescent purple in the afternoon glow before uncapping it with his mouth, the cap firmly between his teeth.
“Wha—”
Zuko lunges.
The next few seconds explode in chaos. Sokka flails wildly, arms flying every which way as he finds himself pinned under Zuko’s palm, a dry and heavy weight that bears down on his chest and refuses to let up. Something ghosts over his neck and across his throat, a whispered touch of a felt tip tickling his skin before Zuko pulls up, smirking as he caps the highlighter.
“There,” he says as he sits back up. “Now that’s more like it.”
Sokka reaches towards his neck, rubbing frantically. His hand comes away purple, highlighter smudged on his fingertips. “Did you just write clavicle? On my clavicle?”
“You just ruined all of my hard work.” Zuko frowns. “Guess I have to do it again.”
Sokka gapes. He can’t really see his neck from this angle, but he’s pretty sure Zuko just wrote “clavicle” across his collarbone in that neat, narrow handwriting of his, the kind that’s the exact antithesis of the stereotypical doctor-scrawl he’s used to seeing on prescriptions.
Zuko uncaps the highlighter again. “Now if you don’t move this time—at least you have another clavicle I can—”
Sokka doesn’t give him a chance to finish, his entire mind focusing on snatching the highlighter away from Zuko’s grasp to preserve the sanctity of his remaining clavicle.
One minute they’re on the couch, the next they’re sprawled on the floor next to the coffee table in a tangle of limbs and flannel and cotton, Zuko pinned beneath Sokka, wide-eyed and winded.
The highlighter rolls away underneath the couch.
Sokka has a distinct feeling of déjà vu, both of his hands planted firmly on either side of Zuko’s head, muscles trembling under the effort of holding his body up at an awkward angle that’s hell on his biceps because he just woke up and everything’s still a bit much to handle, okay? Zuko doesn’t look impressed at all, if his slightly perturbed expression has anything to do with it. It’s like he’s waiting for Sokka to make the next move, probably hoping for him to flop to the side in a disgraced heap of atrophied muscle and exhausted nerves, anything besides trapping his boyfriend to the floor.
Sokka falters.
“Uh—” he begins, mind racing as he tries to come up with a reasonable excuse for why he has his boyfriend spread-eagled on the floor beneath him. “I—”
Zuko gives him a look, the one that screams rebellion and what’re you gonna do about it, Sokka?, the one that shines a feral streak in his eyes, goading Sokka into temptation.
Oh, it’s on.
There’s absolute silence as Zuko stares up at him, unblinking, eyelashes fluttering when Sokka runs a finger across his forehead, gently over whorls of scarred skin, then down, a clean sweep across his forehead, smoothing out a telltale wrinkle or two, past the nasal bridge, dipping into the furrow on the side of Zuko’s nose, concealing lacrimal bone.
This is where he cries, a tiny voice whispers in Sokka’s mind, even as Zuko stares unflinchingly, not a single movement when Sokka swipes his thumb beneath his eye.
Zuko has perfect cheeks, perfect zygomatic bones, perfect freckles that sparkle when Sokka kisses him sweetly, first on his forehead, then on the nose. Kiss, kiss, kiss along a mandibular arch so sharp, it could cut glass. His face is all angles and soft skin—there’s a fragrance, something fruity, like peaches, and Sokka just knows that he’s been using that exfoliating scrub that Ty Lee gave him for Secret Santa, the one he swore he would never touch.
Smooth skin over sleek bone.
Absolutely fucking perfect.
The air hangs lazily, a curtain of uncertainty over the room as Sokka traces a finger up and down the side of Zuko’s throat before pressing his fingertip into the underside of Zuko’s jaw, grinning when Zuko’s pulse jumps under his touch.
Funny thing about the human body, how the head—with its squishy brains and irreplaceable senses—is completely dependent on a haphazard arrangement of bones and flexible cartilage to hold it in place. Seven bones and some cartilage. That’s all that stands between the brain and the body, balancing everything, breathing lungs, beating heart.
Sokka wraps his hand around the back of Zuko’s neck, runs his fingertips along the center ridge and down each bump, down each spinous process of cervical vertebrae—atlas, axis, three, four, five, six, seven—and watches his boyfriend’s eyes go glossy granite.
It’s a good color on Zuko, his pupils midnight black like a galaxy on the cusp of a supernova, the barest hint of amber flame flickering on the edge of his pupils. Zuko’s skin blossoms into a curious shade of dark pink, two spots of cherry red high on his cheeks that could rival the color of his lips when he wets them with his tongue, a flash of pink against white teeth that does something really fucking stupid to Sokka’s brain.
He moves his hand down, settles his thumb against the nape of Zuko’s neck, fingers still tangled in messy whorls of ink that frame Zuko’s face, a careless strand or two curled over his forehead. Sokka’s other hand moves by itself, tucking the stray ringlets behind his ear, fingertips lingering just a second longer against scarred skin.
Ah.
Sokka bends down to kiss Zuko, a chaste kiss on the lips, tentative, gentle. Then again, because he can’t get enough, how Zuko relaxes under him, mouth pliant, lips parted. He tastes like clementines, honey-tart-citrus with a hint of mint, warm and wet and wonderful. It’s too hot, breathable cotton stifling Sokka’s skin as he reluctantly pulls away, eyes fixed on Zuko’s lips, kiss-bitten and glistening like dewdrop-peonies on a foggy morning.
“Shirt off,” he mumbles under his breath as he struggles with his own clothes, bare skin electrifying when he pulls off his hoodie and tosses it behind him. Sokka reaches out, twisting his fingers around the hem of Zuko’s flannel and tugs at it, grinning when Zuko raises his eyebrow and pulls it off, his shirt quickly joining the growing pile of clothes off to the side.
Zuko paints a pretty picture, all tanned skin adorned with the slightest hint of blush, all valleys and ridges of smooth muscle hidden underneath the bulky shirts he likes to wear. His eyes gleam, soft amber hidden beneath long eyelashes as he blinks once, twice, biting his lip for good measure. He’s stunning, a knockout punch Sokka would’ve never seen coming until it crashes face-first against his entire being.
Well, fuck me.
“You really up for that?” Zuko hooks his legs around Sokka’s waist and pulls him in, their hips colliding in a simile of sparks.
“Zuko—” Sokka growls, a guttural rumble undulating under his voice—where the fuck did that come from?—memorizes the way that Zuko stiffens, entire body taut, a string waiting to be plucked. “—don’t tempt me.”
It’s not enough.
It’s never enough, Sokka whispers traitorously to himself before reaching down for Zuko’s hand and bringing it to his lips.
Kiss.
“Distal interphalangeal joint.”
Kiss.
“Proximal interphalangeal joint.”
Kiss.
“Metacarpophalangeal joint.”
Zuko shudders.
Sokka kisses fingers, palm lines, carpal bones strained from years of frenetic writing. His thumb glosses across the tips of short fingernails, blunt and neatly cut, glossy pink in the sunlight with a hint of rose-white cuticle bordered by eponychium. He noses Zuko’s wrist, grips the carpals with his hand, his thumb drawing circles around the ulnar styloid process, the small bump in Zuko’s wrist against Sokka’s fingers.
Zuko’s quiet, save for the rare hitch in his breath when the air flutters in his throat, small coughs masking his gasps as he comes alive with each breath, tiny butterflies escaping between his quivering lips.
“Hold on—” Sokka manages to whisper in between his kisses. “Gimme a sec—gotta grab—”
His gaze never leave Zuko’s eyes, even as he blindly feels around for his backpack for something to write with, only to pull out—
“Why do you have red eyeliner?”
Godsdamn it.
(Sokka’s going to kill Suki.)
It’s a really nice eyeliner, like the ones Sokka’s seen before in CVS, with no signs that it’s ever been used.
“I—” Sokka’s at a loss for words.
The eyeliner burns bright, a perfect liquid red tip when he pulls off the cap.
“It’s pretty,” Zuko smirks. “Not sure if it’s your shade, though.”
“You little—” Sokka brandishes the eyeliner in his hand, annoyed that Zuko’s clearly forgotten who has the higher ground here. “I’m gonna—”
“Do your worst.”
“Famous last words,” Sokka says, even though his heart is beating a million beats a second as he lowers the pen. His hand trembles, the eyeliner wobbling in his hand as he drags a finger across Zuko’s clavicle, along the ridge, to the acromion jutting out from the edge of his scapula. It takes him a second to realize that Zuko’s barely breathing, eyes wide, his entire body absolutely still, until Sokka notices a telltale tremor, a near-silent hum in the air between them when he finally touches eyeliner to skin.
Utter silence.
C, Sokka writes.
The C turns out a bit lopsided, even by his standards, the curve of the letter messy and smearing red as it traverses over Zuko’s left sternocleidomastoid, a taut ridge of muscle that comes to the surface when he tilts his head, lips parted, mouth open in a silent gasp. He can’t tell if his hand is trembling or if Zuko is shivering under his gaze.
L, A, V, I, C, L, E follows, each letter quivering against the tan expanse of Zuko’s collarbone, deep crimson a stark contrast against honey-bronze skin.
“Clavicle,” Sokka breathes into the room, his eyes following the letters across the dip in Zuko’s skin. He watches Zuko swallow, the slight curve of his laryngeal prominence bobbing in his neck, which also does something stupid to short-circuit Sokka’s brain, because it isn’t fair that Zuko’s this attractive while swallowing, of all things.
“Clavicle,” Zuko repeats quietly.
Sokka continues downwards, his eyes following Zuko’s clavicle towards his sternum—sternoclavicular joint—scribbles STERNUM in messy cursive down the center of Zuko’s chest, his head nodding in approval as crimson bleeds into Zuko’s skin and stains it all pretty and messy.
His fingers skip over Zuko’s ribs, undulating between muscle and bone.
“Twelve sets of ribs, but only the first seven are true,” Sokka murmurs out loud, trying to remember the obscure facts Professor Jian likes to mention in class on a whim before devoting an entire section on his exams to these random tidbits to see if students were paying attention. “The last two are floating.”
He braces his hand against Zuko’s chest and feels Zuko’s heartbeat thundering beneath his ribcage, a tiny phoenix shrieking to be set free. Sokka runs his finger along the sternum, downwards, dropping a kiss at the tip of the xiphoid process. It’s laughably simple, the sternum—a flat bone that protects Zuko’s heart from literal heartbreak.
“External obliques,” Sokka murmurs, eyeliner skidding over the expanse of tanned skin. “They help with breathing and bending.”
“Internal obliques run in the opposite direction. Transverse obliques are deep,” Sokka continues. He doesn’t bother labelling them individually because his focus is shot and Zuko is being absolutely distracting, the way he blinks and stares at Sokka like he’s hung the sun, the moon, the stars. OBLIQUE smears into something unintelligible, obscured with each breath Zuko takes, his chest rising and falling.
“Rectus abdominis.” Sokka’s breath stumbles when he makes it to Zuko’s abs, his fingers skimming over the ridges of tendinous intersections concealing hard muscle.
Gods, that’s hot.
Zuko’s not skinny, not by a long shot, his muscles tensing ever so slightly when Sokka traces along his waist, his hips, iliac crest unyielding beneath Sokka’s fingers, the slightest hint of an inguinal crease peeking over the waistband of his leggings. The eyeliner skids over a tendinous intersection when Sokka continues writing.
“Umbilicus.” He wrinkles his nose. “That is so not sexy.”
“And belly button is?” Zuko scoffs. “At least umbilicus sounds fancy.”
“Yeah, sure, if your idea of fancy is a dead language.”
“Don’t like umbilicus?”
Sokka shakes his head. The belly button is arguably the least sexy part of the body. Plus, he doesn’t think Professor Jian is going to test on something so inconsequential. Why bother asking about the belly button when you could torment your class with naming the nine abdominopelvic regions?
“Moving on—” Sokka shakes his head and moves his hand downwards, along rigid muscle, along fiery skin, resting his hand on the waistband of Zuko’s leggings. “Public symphisis—one of the only secondary cartilaginous joints on the—”
His voice trails off, eyes wide and immediately drawn to the curve of Zuko’s erection, how the fabric stretches obscenely over the bulge, straining and tenting against its confines. Zuko watches him with lust-blown pupils and blushing cheeks that turn darker by the minute.
“—entire body.”
Zuko gasps.
Sokka blinks. “You’re—” you’re hard, he wants to say, except the words lodge in his larynx, all coherent thoughts yeeted from his head when he watches Zuko tremble and shake under him, body coiled like a live wire, ready to explode.
“Don’t.” Zuko turns his head, burying his face in the crook of his elbow.
“Babe?” Sokka runs his hand through Zuko’s hair. “Are you—?”
“Don’t say it.”
Another nasty idea manifests itself in Sokka’s brain, and he shifts his body, bending until he hovers right over Zuko’s ear—helix, anti-helix, tragus, auricle lobule—
“Superior mesenteric lymph nodes,” he whispers.
“...”
“Retroperitoneal cavity.”
“... Sokka.”
Sokka leans down and brushes his nose against Zuko’s curls, smelling of sunshine. “Inferior pancreaticoduodenal artery.”
He laughs when Zuko shudders. “You—you like—”
“Shut up,” Zuko hisses, embarrassment clouding his voice. “Don’t say it.”
“Are—are you—you’re turned on by really unsexy medical terminology?” Sokka asks, raising an eyebrow.
Zuko shakes his head and mumbles something under his breath.
“Could you repeat that?” Sokka tries to keep his tone light, like he’s trying to placate a particularly skittish cat.
“—supersexysmart—”
“Say it louder for the rest of the class?”
“—I just really like it when you talk nerdy to me, okay?”
Oh, gods.
Zuko turns for a split second, just enough for Sokka to catch a glimpse of his mortified face, before he turns his head away again.
“Oh, babe.” Sokka takes a second to compose himself, starts thinking about his wrinkly old ex-anatomy professor to calm himself down, because he isn’t sure he can handle himself with Zuko and all his surprises. “C’mon. Look at me.”
“No.”
“Please?”
“No.”
“Please, Zuko?” Sokka pleads.
A minute passes, then Zuko tilts his head, exposing one wary eye, an indescribable look on his face.
“Everyone has—”
“But it’s weird,” Zuko whines, like his secret is something that’s truly dirty and shameful. “And it’s embarrassing as fuck—”
“It’s not dirty.” Sokka takes Zuko’s hand, guides him towards his aching cock, smirking when Zuko’s eyes widen. “It’s hot. Fuck. The things you do to me. Gods, Zuko.”
He lets Zuko touch him, to feel how hard he is, how much he wants it, static friction grazing his nerves with every feather-light touch. He kisses Zuko, deep and filthy, all tongue along blunt teeth—molar, canine, incisor—Zuko’s mouth turns a pretty pink when he pulls away. He rakes his fingers across Zuko’s groin until Zuko keens, a reedy noise that curls in the pit of Sokka’s stomach and smolders there, hot ashes feeding a growing fire.
“Are you going to continue?” Zuko whispers, his voice rough, the slightest hint of a whine bleeding at the edges. His eyes have gone shiny again, clear and dark, a lovely carmine smattered over his cheeks rivalling the eyeliner smeared all over his chest.
The eyeliner clatters to the floor, forgotten.
“Hell yes.”
Sokka kisses him again, swift and hard, one hand cradling Zuko’s head, the other palming him over his leggings, teasing, sliding over thin fabric, sticky and soaked from how wet Zuko is, how needy Zuko is, begging beneath clenched teeth and shivering skin.
“Off,” Sokka growls, one hand slipping past the waistband and tugging off Zuko’s leggings and underwear in one go, stifling a gasp when he sees how wet Zuko is, precome leaking in feeble spurts, pearling down the length of his cock, long and narrow and nothing like Sokka’s own. Just the sight of how utterly gone Zuko looks is enough to make Sokka so hard it hurts, tight against his briefs, all the blood in his circulatory system going haywire.
“Inguinal,” Sokka mutters as he traces a nonsensical pattern across Zuko’s hips. “The sacrum is right above the coccyx, right?”
Zuko whimpers.
“Hip joint—classic example of a ball-and-socket joint—great for mobility—”
Zuko shudders.
Sokka steals a moment just to worship him, bless the curves and edges, takes Zuko’s cock in his hand and strokes gently, all rosy-tipped and throbbing, heat pouring off his skin in waves. “So sperm matures in your testes, and then it goes up through the epididymis, then to the vas deferens—”
“Yes, Sokka.” Zuko narrows his eyes. “There’s going to be a vast difference between us if you don’t shut up and fuck me already.”
“Oh my gods.”
Zuko blushes.
Sokka can’t get out of his sweatpants fast enough, nearly tangles the fabric in an undignified knot when he finally manages to pull it all off before diving back in for a kiss, one hand coming around to tweak Zuko’s nipple, listening to his desperate cries, rutting against Sokka’s stomach, until Sokka reaches for his hand, kisses his knuckles, brings it down to their weeping cocks.
“That’s it, babe, you know how I like it.” Sokka can barely contain himself as he watches Zuko wrap his fingers around their cocks, long, thin fingers—doctor’s fingers—moans when Zuko does something wicked with those fingers of his that sends Sokka into hyperdrive, arms locked around Zuko’s waist, cupping his ass, squeezing, kneading gluteus maximus between his fingers, teasing, teasing until he brushes his thumb against Zuko’s hole. Zuko’s grip tightens, delicious heat scorching between them.
“Babe?”
“Sokka—”
Sokka rubs a finger against Zuko’s perineum, traces a slick circle, slides one finger in, then another, nearly comes at the sound of Zuko howling into his chest, the feeling of Zuko’s fingers frantically pumping up and down. He pushes deep, deep until he feels it, feels for the spindly network of the prostatic plexus, and crooks his fingers.
A cry.
Zuko shatters, comes with a whimper, sticky and warm between their bodies, his entire body spasming, shuddering in the remnants of the aftershocks coursing through his body. He writhes on the floor, fist tightening around their cocks, and Sokka buries himself deep in Zuko’s grip until he crashes, shaking and nearly whiting out himself, tachycardic heartbeat roaring through his ears at full throttle.
The ensuing silence is deafening, except for the occasional gasp as Sokka touches base with reality, his breath steadying, rolling under his rib cage when he collapses on his side, taking care not to squish Zuko underneath him.
“Babe, you still with me?”
“Mhm.” Zuko grumbles, hair floating around him like a godsdamn halo as he curls up, wraps his arms around Sokka’s chest and breathes. “Fucking hell.”
They stay like this for a while, the afternoon quickly blending into shimmering sunset, throwing blades of tangerine, lemon, peach-colored light into the room and over Zuko’s face. His lashes flutter when Sokka presses a kiss to his forehead.
“Hey, babe.”
“Hm?”
“Did you know that the perineum is innervated by the pudendal nerve?”
“I—”
“And perineurium is the layer that surrounds fascicles, which are bundles of—”
“Sokka.”
“Hm?”
“Shut up.”
Internally, Sokka high-fives his brain, still giddy on endorphins.
(Take that, Professor Lo.)