The pink string lights in your dorm cast everything in a soft glow, turning your notes into watercolor shadows. You sit cross-legged on your bed, staring at the skeletal system diagram. Phalanges, metacarpals, carpals. They all blur together into a mess of Latin that refuses to stick, sliding off your brain like water off glass.

The October heat is unreasonable, heavy in a way that makes you question whether fall will actually arrive. Your box fan pushes the humid air into lazy circles.

Satoru is sprawled beside you, back against your mountain of frilly pillows, glasses slightly crooked, braces flashing when he chews the end of his pen. His NASA hoodie is half-zipped, showing the collar of his t-shirt underneath, and his sweatpants are the comfortable kind he only wears around you. He’s supposed to be studying quantum mechanics; there is a textbook open on his lap, equations scattered across the page in his messy handwriting, but he keeps glancing at you instead.

You’ve been best friends since you were seven. You’ve kissed him exactly once, six weeks ago in this same bed, when the August heat was even worse, and you were worried about going on a date with Sukuna. Practice kissing, you’d called it, though you didn’t go on that date, and neither of you has mentioned kissing since.

Except you think about it constantly. The way his hands felt on your waist. The careful pressure of his mouth. The soft sounds he made when you’d straddled his lap and ground against him until he came in his sweatpants, shaking and whimpering your name.

You think about it so much that you can barely focus on anatomy.

You’ve reread the same page four times now. Your highlighter hovers over the skeletal system diagram without actually highlighting anything, suspended in indecision. You keep making little sounds of frustration, huffs, and sighs that make your coils bounce where they frame your face.

You’re still in what you wore to class, the pink mini skirt that’s ridden up slightly from sitting, matching crop top, glossy lips that you reapplied between lecture and coming back here, gold hoops catching the afternoon slight. 

Midterms are in two days, and you’re nowhere close to ready, nowhere close to understanding why anyone needs to memorize two hundred and six bones.

“You’re gonna burn a hole through the page,” Satoru says finally.

You turn to look at him. He’s pushed his glasses up, leaving a small indent on the bridge of his nose. It’s clear he’s been watching you for some time.

“What?”

“You’ve been staring at the skeletal system for twenty minutes.” He tilts his head.

“I don't–” you gesture helplessly at the textbook, at the color-coded notes that aren’t helping. At the flashcards that you made, which are equally useless. “It’s all just…Latin. My brain won’t retain any of it.”

He sits up. “Want help?” He taps the textbook with one long finger. “You learn better with hands-on stuff anyway. I’ve known you long enough to know that.” 

And he has. Fourteen years of friendship means he knows how you study, knows that you need movement and interaction instead of static memorization. “Cmon, we’re doing this the fun way.”

He settles behind you, long legs on either side of you, and suddenly you’re bracketed by him, his chest a warm presence at your back, his arms loose around you, every point where you’re almost touching feels electric despite the heat.

“Is this okay?” he asks quietly, and you can feel his breath against your neck, warm and careful.

“Yeah,” you manage.

His hand finds yours, lifting it carefully. His fingers are long and warm, and when they wrap around your wrist, you feel your pulse jump.

“Start simple,” he says, and his voice has gone lower, more intimate. “These are your phalanges.” His fingers trace each of yours in turn, over your pink polish, along each knuckle, learning the shape of them. “Distal, middle, proximal. Fourteen in each hand, twenty-eight total in your body.”

“Say it,” he prompts softly.

“Phalanges,” you manage. “Distal, middle, proximal.”

“Good girl.” The praise makes something low in your stomach tighten. His fingers trace down to your palm, and the touch is calculated. “Metacarpals. Five bones in the hand connecting your wrist to your fingers.”His fingers map each one through your skin, pressing gently, and you have to fight to keep your breathing steady. “Can you feel them?”

“Yes,” you breathe.

“Then your carpals. Eight little bones right here.” He presses where your hand meets your wrist, his thumb making small circles. “Remember the mnemonic? Some lovers try positions that they can’t handle.”

The words make you acutely aware of everything you’re almost touching, your back nearly against his chest, his thighs bracketing yours, the careful inches of space he’s maintaining.

“That’s terrible,” you say, but your voice lacks conviction.

“But you’ll remember it.” His breath ghosts across your neck, and you shiver involuntarily. “Scaphoid, lunate, triquetrum, pisiform, trapezium, trapezoid, capitate, hamate. Say them for me.”

You recite the words, stumbling slightly over triquetrum, and he rewards you by letting his hands slide up your forearms. The touch is impossibly slow, his fingers learning the shape of your radius and ulna through your skin.

The fan turns overhead. October sunlight pools golden on the floor. Outside, someone is laughing, the sound distant and unimportant.

“Is this okay?” he asks quietly.

“Yeah. Don’t stop.”

His hands continue their path upward. “Radius and ulna. Two bones in your forearm. His fingers trace the length of both with aching thoroughness, like he’s memorizing you.”The raidus is on the thumb side. Ulna on the pinky side. They allow your wrist to rotate.” He demonstrates, turning your hand slowly, and the motion is so intimate it makes you dizzy.

You lean back without meaning to, closing the minuscule distance between you, and your back meets his chest. He makes a soft sound. His free hand comes to rest on your hip, just holding you there, and the touch burns through the thin fabric of your crop top.

“Humerus,” he continues, and his voice has gone rough around the edges. His hands slide up your upper arms, over bare skin, and his touch is reverent. “Longest bone in your arm. Connects your shoulder to your elbow.” He traces the full length of it, and you can feel his chest rising and falling against your back, can feel that his breathing has picked up, too.

“Satoru,” you whisper, not sure what you’re asking for.

“I’ve got you. Just keep learning” His hands move to your shoulders, and the touch is less clinical now, more exploratory. “Clavicle. Your collarbone.” His fingers trace the bones, and when he leans forward, close enough that his lips almost brush your shoulder, you make a soft sound you can’t contain. “Did you know that the clavicle is the most commonly broken bone in the body?”

“No,” you manage.

“Mmm. Very delicate.” His fingers follow the line of it, and you’re not thinking about anatomy anymore, not thinking about midterms or med school or anything except six weeks ago and the way his hands feel on your skin.

“And your scapula. Shoulder blade.” His palms spread across your back, touching you through your thin crop top, and the warmth of his hands seeps into your skin. “It’s a flat triangular bone. Can you feel the edges?”

You nod, not trusting your voice, hyperaware of his hands on you, of how this stopped feeling like studying several minutes ago and started to feel like something else entirely. Something that makes your heart race, your breathing shallow, and your skin feel too tight.

“Your ribs next,” he says, and his hands slide around to your front. You hold your breath. “Twelve pairs. Twenty-four bones.” his fingers splay across your ribcage, just below your breasts, and you can feel your heart pounding against his palm. “The top seven are your treu ribs, they connect directly to your sternum.” He traces each one with excruciating care.

“The next three are false ribs,” he continues, fingers sliding lower. “They connect to the cartilage of the ribs above them. And the bottom two are floating ribs.” His hands rest just above your waist. “They don’t connect to anything. Just float freely. Protectiction without constraint.”

His words feels weighted with meaning.

“Your sternum.” One hand moves to rest at the center of your chest. “The breastbone. It protects your heart and lungs.” His hand warm through your top, and you can feel your heartbeat against his palm, know he can feel it too–evidence of how affected you are.

“Keep going,” you say.

His hand slides to your back. “Vertebrae.” His fingers find your nape and trace down your spine, counting. “Cervical, thoracic, lumbar, sacral, coccyx.” Each word is punctuated by his fingers walking down; the intimacy of it makes you shiver.

“Turn around,” he says quietly. “I need to show you the anterior view.”

You turn slowly in the space between his legs, and suddenly you’re facing him, close enough to see the way his pupils have dilated behind his glasses, close enough to see his lips part slightly when you settle.

His thumbs stroke small circles over your skirt. “Okay to keep going?”

You nod.

“Your cranium.” His hands slide up slowly, over your ribs, your shoulder, until his fingers thread carefully through your hair. “Eight bones fused together to protect your brain.” His touch feather-light as he traces your skull. “Frontal, parietal, temporal, occipital, sphenoid, ethmoid..” Each bone is mapped with gentle fingers.

His hands slide down to cup your face, thumbs stroking your cheekbones. “Zygomatic bones. Your cheekbone.” He traces them with such tenderness. “Maxilla. Your upper jaw. And the mandible.” His thumb brushes along your jaw, tilting you face up slightly. “Your jawbones. Only movable bone in your skull. Would you like to demonstrate for me?”

You open and close your mouth and his thumb slides across your bottom lip, you momentarily forget how to breathe.

“Your teeth,” he says, gaze fixed on your mouth. “Thirty-two of them. Incisors, canines, premolars, molars. Hardest substance in your body.”

His thumb is still tracing your lip and the touch is making it very hard to think.

You close the distance.

It’s different from six weeks ago. Less tentative. You know what he tastes like now–mint gum and something underneath that’s just him. Know the feel of his braces, the way he kisses careful at first before losing control. 

His hands are still cupping your face and he kisses you like he’s been waiting for permission, like he’s been thinking about this just as much as you have. You press closer, and he makes a soft sound against your mouth that emboldens you. Your hands find his hair and his grip on your face tightens, and when his tongue slides against yours you taste him.

When you deepen the kiss, your tongue slides against his. You lick into his mouth like you're trying to taste every part of him, and the small whimper he makes only encourages you. You shift to straddle his lap and settle your weight on him. His hands immediately go to your waist, gripping, and when you roll your hips experimentally you feel him already starting to harden beneath you.

“Missed this,” you murmur against his mouth.

“Yeah?” His voice is rough. “You didn’t mention it. After. I thought maybe–”

You kiss him again, harder this time, and grind down on him deliberately. The sound he makes is half-gasp, half-moan.

You kiss down his jaw–mandible, you think–and find the spot below his ear that made him whimper last time. When you bite down gently, his hips jerk up involuntarily.

“Cervical vertebrae,’ you murmur against his neck, kissing lower. “Seven bones.”

“Good memory,” he gasps.

You push his hoodie off his shoulder and he helps you, shrugging out of it. Then you’re pulling his t-shirt over his head and suddenly he’s bare frome the waist up, pale skin and lean muscle and the rapid rise and fall of his chest.

“Clavicle,” you say, pressing a kiss to his collarbone. “Sternum.” you kiss the center of his chest. “Ribs.” You kiss lower, counting, and his hands fist in your pink sheets.

When you reach his hip bones, you pause, looking up at him through your lashes. His glasses are already fogged and his lips are parted and he’s looking at you with such want it makes your head spin.

“Keep going?” you ask.

“Please,” he breathes.

Your hands find the drawstring of his sweatpants. You untie it slowly, watching his face, and hook your fingers in the waistband. He lifts his hips to help you pull them down along with his boxers, and then he’s bare beneath you

He’s already hard, flushed and straining, and when you wrap your hand around him tentatively he makes a sound that’s almost pained.

“Is this okay?” you ask, wrapping your manicured hands around the base. Your pink nails look obscene against his pale skin.

“So okay,” he gasos. “You don’t have to–”

“I want to.” You stroke him once, slow and probing and watch his eyes flutter closed. “Will you keep teaching me? Keep naming bones?”

His eyes snap open, wide behind his glasses. “You want me to–while you–”

“Yeah.” you lean down and press a wet open-mouthed kiss to his hipbone. “Ilium. You whisper against his skin. Part of the pelvis.”

“Smart girl,” he breathes.

You lick a stripe up his length, base to tip, and he whimpers. Your tongue swirls around the head and you taste salt, the evidence of how affected he already is.

“Keep going,” you prompt.

“The–the sacrum,” he manages, voice strained. “Triangular bone. Five fused vertebrae–oh god–”

You take him into your mouth; just the head at first, getting used to the weight of him on your tongue. You’ve never done this before, have no idea if you’re doing it right, but the sounds he’s making suggest it doesn’t matter.

You try to take him deeper, experimenting, but the angle is wrong. Your teeth graze him accidentally and he hisses.

You pull off immediately. “Im sorry.”

“Its okay,” he says quickly, his hand gentle in your hair. “You didn’t hurt me. Just cover your teeth with your lips. Like this.” He guides you back. “And you don’t have to take me deep. Just whatever’s comfortable.”

You try again, more careful this time, lips wrapped over your teeth. When you take him back into your mouth and hollow your cheeks slightly, he groans.

“That’s good,” he encourages, breathless. “You’re doing so good. You can use your tongue–yeah, just like that,” his eyes roll to the back of his head.

You find a rhythm, bobbing your head slowly. Spit already drips down you chin as you bob, hand stroking what your mouth can’t reach. The wet, sloppy sounds fill the room.

Your other hand braces on his thigh and you can feel him trembling beneath your palm.

“The coccyx,” he gasps out, struggling. “Your tailbone. Four fused vertebrae–”

You swallow around him, taking him as deep as you can, nose brushing the soft hair at his base. His words dissolve into a broken moan. His hand tighten in your curls–not pushing, never pushing, just holding you like you’re the only thing keeping him grounded. His thighs shale under your palms.

You pull back to catch your breath, letting saliva pool in your mouth before taking him again, and the wet sound it makes is sinful. Your hand works him in tandem with your mouth now, slack with spit and precu that’s leaking steadily from his tip.

“The pelvis,” he tries, but his voice is wrecked. “Three bones. Ilium, ischium, pubis. They fuse–they fuse during–”

You look up at him through wet lashes, maintaining eye contact while you work him, and the sight of him nearly undoes you. His head is thrown back against your pillows, exposing the long line of his throat. His glasses are completely fogged. His mouth is open, lips red and swollen from kissing, and small sounds keep escaping him that he doesn’t seem to have any control over.

You can feel him getting close, his thighs tremble harder, his breathing has gone reggae and uneven, and when you swallow around him aagin his whole body goes taut.

“Not gonna last,” he warns, voice breaking.

You hum around him, the vibration making him curse, and push your mouth down as far as it will go. Your nose nearly tocuehs the soft skin of his lower stomach and you feel him pulse heavy on your tongue.

“Can’t take it,” he whimpers, and he’s practically hunched over now, rigid like he’s tryin to hold back. “Can’t. Mouth feels so good on me. Like you’re trying to kill me–”

You pull back slowly, tongue dragging along the underside, before taking him deep again. The rhythm you set is already stead and calculated, designed to unravel him completely, and it’s working like a charm. His hand in your hair has gone tight enough to sting and his hips keep shifting, like he’s fighting the urge to thrust.

“Don’t look at me like that,” he gasps when you meet his eyes again, but there’s no real bite in it. Just desperation. His free hand comes to cup your cheek, thumb stroking over the bulge his cock makes there. “Please—I’m so close–”

His glasses are sliding down his nose, braces flashing as he pants. You look up at him through your lashes and take him to the back of your throat. You swallow around him again and that;s what breaks him. He comes with a wrecked sob, hips stuttering, tears slipping from the corners of his eyes. You work him through it, swallowing what you can, hand still stroking as he pulses in your mouth.

You pull of gaspsing, lips swollen and shiny with spit and him. He’s staring at you like you’ve hung the stars. His chest is heaving, flushed pink down to his ribs, and there’s a light sheen on sweat on his skin despite the fan.

Before you can speak he hauls you up and kisses you–nasty , filthy, open mouthes. His tongue licks into your mouth like he’s tasting himself on you, braces scraping your lip, spit slick between you. He whimpers into the kiss, hands fisting your curls, devouring every noise like he’s starving. It’s messy and wet and perfect: tongues sliding, teeth clicking, his come and your gloss mixing until you’re both moaning into each other’s mouths.

When he breaks the kiss strings of spit connect your lips. He trails his lips down your jaw, you’re both breathing hard.

“Your turn,” he says against your neck.

“What?” 

“Your turn.” He’s already working at your skirt. “Let me make you feel good. Let me taste you.”

“You don’t have to–”

“I want to.” He gets your skirt off and then your underwear, and you’re suddenly bare from the waist down, exposed in the pink glow of your string lights. “Want to make you feel as good as you just made me feel.”

He settles between your legs, hand on your thighs, spreading them wider. The way he’s looking at you–focused and hungry-- makes heat flood through you.

“Hey.” His hands stroke your thighs gently. “We’ll go slow. You tell me if you want to stop, okay.”

“Okay,” you whisper

“Keep teaching me,” you add, trying to sound braver than you feel.

He grins, braces flashing. “The pelvis,” he says pressing a kiss to your inner thigh. “Formed from the ilium, ischium, and pubis.” another kiss, higher. “The acetabulum.” Higher still. “Where the femur connects.”

Then his mouth is one you and–

Oh.

The sensation is foreign, so strange that you nearly jerk away. His tongue is warm and wet and slimy in a way you weren’t prepared for, the texture completely different from anything you’ve felt before. It’s weird. Almost uncomfortable in its unfamiliarity.

But then he does something with his tongue, a slow, meticulous stroke, and pleasure sparks through you so sharp it makes you gasp.

“Okay?” he asks, pulling back slightly.

“Weird,” you admit breahtlessly. “But good. Keep going.”

He does and you start to understand it. The wet slide of his tongue is strange, yes, bit it’s also perfect in a way you can’t articulate. He’s methodical, learning what makes you gasp and what makes you arch off the bed.

When he finds your clit and circles it with the tip of his tongue, the sensation makes your thighs tremble. It’s so much, too much, the wet warmth of his mouth combined with the focused pressure. You can’t decide if you want to pull away or press closer.

“Satoru,” you gasp, and your hand flies to his hair.

He hums against you, the vibration sending another shock of pleasure throught you, his hands slide up to hold your hips down when they start to shift. The slimy warmth of his tongue felt weird at first but now it’s all you can focus on, the way it moves against you, broad and flat and then pointed and precise, learning you.

When he slides one long finger inside you, you sob. The intrusion is careful and he crooks his finger immediately to find that spot nside you that makes you see stars.

“There?” he asks, pulling back just enough to speak, and you can see your arousal glistening on his lips again.

“Yes,” you manage. Right there. Don’t stop–”

He doesn’t. He adds a second finger, stretching you carefully, and his mouth returns to your clit. When he finds that spot inside you once again he abuses it.

He’s paying attention to what makes you react, what makes your grip on his hair tighten, what makes those breathy sounds escape your throat. When he finds a particular rhythm with his tongue, quick flicks followed by slow, firm pressure, you feel your orgasm start to build.It feels oh so good. His tongue is sloppy yet calculated

“Close,” you gasp, “i’m so close.”

He doubles his efforts, fingers pumping faster, tongue working you relentlessly. His free hand slides up your body to plan you breast through you top, thumb brushing over you nipple, and the added stimulation pushes you over the edge.

You come with a cry, your whole body tensing, inner muscles clapping down on his fingers . The pleasure is so intense it borders on painful, radiating out from where his mouth is still moving against you, working you through it with gentle attention.

When it becomes too much, when you’re whimpering and pushing at his head from oversensitivity, he finally pulls back. His glasses are even more fogged than before and his face is wet with you, his chin, lips, even his nose glistening in the pink light.

“Good?” he asks, bringing you into another kiss.

“So good.” 

He laughs and presses a kiss to your forehead. He then settles beside you and pulls you into his chest. You turn in his arms to kiss him properly, tasting yourself on his tongue and think failing anatomy wouldn’t be the worst thing if it meant more study sessions like this.

Two days later, you text him from outside the exam hall:

You: I got a 97

Satoru<3: told you

Satoru: what did you miss?

You: The hyoid bone. We never got to that one.

Satoru: guess we’ll have to have another study session