Archive of Our Own

There’s a girl standing in the snow. 

Or at least, that’s Senku’s first assumption. It’s hard to see clearly through the foggy windows of the cafe she’s cozied up in. Really, Senku doesn’t have time for people-watching with so many deadlines looming over her, but it’s hard to return her attention to her laptop screen while she’s witnessing such blatant stupidity.

While the rest of the city hunkers down inside their homes to escape the snowstorm unfolding outside, the girl in question stands with her arms wrapped around herself. She’s shivering, alone under the light of the bus shelter. The structure’s all but useless when the wind’s blowing this hard. 

She’s swaddled in a black puffer jacket, with the hood pulled over her head, by all means unidentifiable. It ends at her waist; the kind of jacket that serves no practical purpose when it’s this cold out. Underneath, Senku can make out long legs clad in sheer black tights and boots that blend in with the silvery snow dusting the ground. She’s pulled matching leg warmers up her calves, but Senku doubts they do anything to guard against the wind chill. 

She’s been standing there for at least eight minutes. Senku’s been keeping count since she first caught sight of her. She isn’t interested in whoever she is or wherever she’s going. It’s just—

The bus the girl is waiting for stops running at nine o’clock. It’s nine-fourteen now, and the snow shows no signs of stopping. The closest functional bus stop is fifteen minutes away, but there’s no way she’ll make it there, dressed like that.

Everything about this stranger screams irresponsible. Who doesn’t check the weather forecast before leaving home? Hell, the rapidly accelerating winds and spike in humidity should have spelled it out clearly enough. 

The girl shivers again and Senku clicks her tongue, oddly frustrated.

Why is she still watching? This isn’t any of her business. Senku has a lot of work to do today, which is precisely why she’s trapped herself in this cafe. They’re open all night and Senku plans to take full advantage of that. Here, neither her father nor her persistent best friend can distract her. Plus, everyone in this cafe knows better than to bother her. She’s come here often enough to have a designated seat, tucked away from the busy counter. 

The employees don’t pay her any mind, no matter how long she overstays. They don’t take any offense when she stops ordering coffee and starts pulling energy drinks out of her backpack. And no matter what time of day Senku comes in, her table’s been freshly wiped clean, like her presence was expected.

But Senku can’t appreciate any of that when her laptop screen is blank in front of her. The cafe is emptier than usual today— there isn’t anywhere to look but out the window.

If the girl outside freezes to death, will the law consider it negligence on Senku’s part? Watching this play out might be in her best interest. Legally speaking.

Another full-bodied shiver. Senku grits her teeth. 

She shouldn’t be able to see the motion so clearly from here. This girl must have a flair for the dramatic.

She’s ten billion percent exaggerating.

So why is Senku picking up the coat draped over the back of her chair? Why is she shoving her arms through its sleeves and zipping it up to her neck? As Senku tucks the ends of her braids under her collar, she sighs and decides she needs to spend less time with Taiju.

She doesn’t bother grabbing her backpack or even packing up her laptop. There’s no one else here right now, and she knows the barista will keep an eye out.

When she tries to push the door to the cafe open, she finds it firmly shut. It doesn’t budge. Senku blinks, then presses herself against it, using her body weight to fight against the immovable obstacle in front of her.

The door finally swings open and Senku realizes why it had been so difficult to move. The wind had forced it shut.

As she takes a tentative step outside, a gust of icy air nearly knocks her off her feet.

Why is she doing this again?

Senku brings a hand up to shield her face and tries to locate the girl she’s come all the way out here for. It's harder to see now, what with the wind stinging her eyes and shards of ice embedding themselves in her face. 

Ah. There’s the stranger, still trembling in place.

Senku crosses the road without looking, taking careful steps to avoid slipping on the ice. It only takes her a few seconds to reach the other side. 

“Hey!” Senku yells as she approaches. She doesn’t usually do that. She doesn’t stop to wonder why she’s putting in so much effort now. Even she’s allowed to feel a little humanitarian, once in a while. She cups her hands around her mouth before continuing. “That bus stops running at nine. You’re gonna freeze to death.”

Finally, as Senku’s almost an arm’s length away, the girl she’s been staring at turns around. As she does, the hood slips from her head, and tousled dark and white hair are the first thing Senku sees.  

“Oh?” says a lilting voice— fuller than Senku remembers it but undeniably familiar. “I thought—”

When the girl’s eyes meet Senku, she feels herself stiffen, chilled to the bone in a way that has nothing to do with the snow falling all around her. The girl’s eyes are narrow and blue, lined with long dark lashes and shining with mirth. Senku remembers what it feels like to be looked at like this—somewhere in the back of her mind, she can recall this curious, amused gaze. She knows that smile intimately well. 

The name spills from her mouth before she can stop to think about it. “Asagiri Gen?”

Gen’s eyebrows furrow in concentration, as she takes a second to scrutinize the not-quite stranger standing across from her. Senku watches her eyes widen with recognition.

“Senku-chan?” It’s faint, nearly overpowered by the wind, but it hits Senku like a blow to the chest. She hasn’t heard that in a while.

“You’re…” Senku hesitates, like saying her thoughts aloud might negate them somehow. “You’re here.”

Gen nods, mouth still parted in surprise.

It’s been years, ages, but all Senku can think is, she looks the same. Sure, her hair is different— split into black and white instead of plain jet black— but it’s still styled the same. Still longer on one side. It suits her.

“Since when are you in town?” Senku asks, when it’s clear Gen won’t say anything else. Senku remembers her being wordier than this.

“Since earlier this year,” Gen admits breathlessly. It could be shock. It could be the cold. There’s moisture beading on her cheekbones, shining under the glow of the streetlights. Her eyelashes are clinging together, wet with snow. Her nose and cheeks are flushed pink.

Senku quickly looks away. 

“I didn’t know you were still…” Gen’s voice is nearly swallowed by the wind.

“Yeah,” Senku says. “I’m still here.” Senku could've left the city she grew up in, but she didn’t. She doesn’t regret it. “More importantly, why are you outside when it’s…?”

“I was visiting a friend. I didn’t think it would get bad so quickly.” Gen shakes her head. “Really, it’s not important. How are you, Senku-chan?”

The longer Gen speaks, it becomes more and more obvious that she’s fighting to keep her voice steady. As soon as she finishes, her teeth start chattering again.

“Cold,” Senku says dryly. “Better than you though.”

Gen offers her a bashful smile. “I’m sure. I really wish we could catch up but I should probably find a way home before it gets worse.” Her eyes flick back toward the bus stop and she sighs. “Do you know where the closest functional bus stop is?”

Senku looks at her again, slowly, from head to toe. “No way you’ll make it there.” She clicks her tongue in disapproval when she notices the way Gen’s buried her hands in her pockets. “You’re not even wearing gloves.”

Gen’s smile becomes strained. “A taxi then?”

“The roads are icy and the snow’s blowing too damn hard to see anything. Don’t take a taxi.”

“Well, do you have a better suggestion?

Senku nods. “Come with me.”

“What?”

“Didn’t you wanna catch up?” Senku points at the cafe she was just inhabiting. “It’s warm inside. You can wait out the storm with me.”

It’s a perfectly sound suggestion, but Gen hesitates. “I probably shouldn’t…”

Senku blinks. Gen looks and sounds the same, but she seems less indulgent than Senku remembers. Is it a symptom of the four years they’ve spent apart?

Well, Senku isn’t going to beg Gen for her time. She’s an adult now. She’s better than that. She won’t—

“Why not?” The question leaves Senku’s mouth without permission.

“It’s… late?” Gen offers. Senku’s not buying it.

“This place is open all night. It’s probably your best bet.” But Senku knows where to draw the line. She learned from the best.

“But suit yourself,” she says, before turning on her heel.

She takes one step away. Then another. The snow crunches under her feet. Senku makes her way back to the road she just crossed without turning around or even glancing at Gen once.

She’s halfway there when she hears the hurried footsteps of someone running after her. Senku grins, but she doesn’t stop walking.

“Okay, wait, Senku-chan! I’m coming!”

The first time Senku met Gen, she was instantly on guard. Something about the way Gen looked at her, or anyone else, was unnerving. Like she meant to pick Senku apart with her gaze alone.

The last time she saw her, a little after Gen’s graduation, Senku remembers feeling unmoored. Like the world was about to become unpredictable— a little less certain without Gen waiting outside her classroom, or by her locker, or next to the school gate.

As Senku pulls off her coat inside the familiar warmth of her favorite cafe, she isn’t quite sure how to feel. Next to her, Gen sighs in relief, rubbing her hands together while looking around the interior. The tables and chairs are made of light-colored wood, and it’s decorated sparsely. The lighting is golden and warm.

The cuffs of Senku’s sleeves are wet from the snow, so she rolls them up her forearms. When she looks up, she finds Gen’s eyes abruptly darting away from her. A tiny shiver runs through her.

Gen follows her lead before Senku can dwell on it. Under her jacket, she’s wearing a deep purple sweater, pulled on top of a black high-necked shirt. Paired with her pleated skirt and tights, she’s dressed for an autumn photoshoot, instead of a winter storm. Impractical, Senku thinks to herself again, like her eyes aren’t lingering on every curve.

Senku’s wearing a ratty flannel she stole from her old man and her most comfortable pair of sweatpants. She smiles. The contrast feels nostalgic.

Senku extends her arm, offering to take Gen’s jacket without thinking. Gen hands it to her, then stops to stare at Senku when she realizes what just happened. Gen’s still taller than her. Senku really had no chance of outgrowing her. But even from below eye level, she can see how Gen’s hair’s been mussed up by the wind. The boundary between the black and white strands of it is messy.

So with her unoccupied hand, Senku reaches out and fixes the part of Gen’s hair. It would bother her if she didn’t. All the while, Gen watches her with wide eyes.

Satisfied with her work, Senku steps away to hang their coats on the rack against the wall. She turns to find Gen still standing, despite the chair pulled out in front of her. Gen’s studying the counter, where the barista’s seated on a stool, with headphones pulled over his ears. Gen picks her purse up off of the table and slings it over her shoulder.

“Where are you going?”

“The least I can do is get you something to drink,” Gen tells her. “I’d be a sorry excuse for an upperclassman if I didn’t.”

“We’re not in school anymore.” And Gen knows that Senku hates stuffy formalities, but still, she shoots her a smile over her shoulder.

“Are you really gonna turn down a free drink?” Then Gen makes her way toward the counter before Senku can say something embarrassing, like yes, just stay here.

Senku watches Gen’s demeanor change in front of her eyes. Despite being perfectly warm, she starts shivering— a slight but noticeable tremble. She crosses her arms over her chest.

When the barista finally takes note of her, he pulls his headphones down and eyes her in concern.

There’s a tremor in Gen’s voice when she asks, “Are you guys r-really open all night?”

The barista nods. “Yeah. We’re open twenty-four seven.”

Gen sighs in feigned relief. “I’m so lucky to have found this place,” she says quietly. “The buses stopped running and I was afraid I’d freeze to death.”

Senku can’t see her face from here, but she can imagine the expression she’s wearing. She’s probably meeting the barista’s eyes, with her lips pursed and eyebrows slanted down, the picture of earnest gratitude. 

And the barista falls for it hook, line, and sinker.  “Let me get you a hot chocolate. Something to warm you up.”

Gen tucks her bangs behind her ear, before she says,“That would be lovely, thank you.” Then she slides her purse off of her shoulder and digs around for her wallet, in an exaggerated motion Senku can’t help but wince at. As expected, the guy at the register stops her.

“No, don’t worry about that. It’s on the house. You look like you need it.”

Gen’s voice takes on a sugary note that grates on Senku’s ears. “You’re too sweet. Seriously.”

Then she stands in front of the counter, shamelessly watching the barista mix powdered chocolate with hot water and steamed milk, asking him how long he’s been working here and how he’s finding night shifts.

This is familiar, sure, but Senku isn’t feeling especially nostalgic watching this no name barista scribble the digits of his phone number onto the paper cup he’s handing Gen.

The torture finally comes to an end when Gen waltzes back to their table, hot chocolate in hand.

She places it on the table in front of Senku. “For you, my dear,” she sings, like she’s offering Senku a thoughtful gift. Senku tries her best to quell the immediate, full body-reaction she has to the old pet name.

“So that’s what you meant by free drink,” Senku scoffs.

Gen pouts. “Well, if you don’t want it—”

Senku picks up the cup before Gen can even finish the sentence. She’s never particularly liked hot chocolate, but if it’ll keep Gen from drinking it, she’ll drain the whole cup. She looks over Gen’s shoulder, trying to meet the barista’s eye as she sips at the drink, but he seems absorbed in his phone.

Oh god, she thinks, disgusted with herself. She’s acting like a teenager again.

She reminds herself not to take the interaction too seriously. Gen’s always been like this.

The first time they’d met, Senku had been in serious trouble for setting off a tiny explosion while conducting an unauthorized experiment in their high school chemistry lab. Apparently, tiny was subjective.

Yuzuriha had immediately enlisted the help of Asagiri Gen, the upperclassmen in her crafts club who was supposedly on good terms with every teacher at their school. Senku doesn’t know what she’d expected. Just that Gen, with uneven dark hair and half a dozen silver piercings along the shells of her ears, was anything but.

“Dear Senku-chan is all alone, you see,” she’d said to Senku’s chemistry teacher, softly, like it caused her personal pain. Like she hadn’t just met Senku, and made the connection to Ishigami Byakuya, the astronaut, five minutes ago.

“She misses her father so much.”

Senku stood behind her, blank-faced. When Gen nudged her shoulder, she tried her best to look sad. Luckily, her teacher’s eyes were on Gen rather than Senku’s lackluster performance.

“Science helps her feel close to him,” Gen said, so seriously. “You wouldn't deny her that, would you?”

Senku had to bite her lip then, to stop herself from bursting out into uncontrollable laughter. No way Gen expected that to work.

But it did. Senku was let off easy, with just a week of extra chores, and continued full access to the lab she’d nearly burned down. And a brand new friend, who was about to become the bane of her existence. Not that Senku knew that then.

Across the table, Gen claps her hands and brings Senku back to the present.

“So, what have you been up to?”

“College,” comes Senku’s blunt response.

Gen hums. “You know, I always thought you’d graduate early.”

“I would’ve if I wasn’t doing a dual degree.”

“Oh, let me guess,” Gen taps her chin. “Astrophysics and…”

“Chemistry,” Senku finishes. “With a specialization in synthetic chem.”

“Of course. I’d never forget your love of making things explode.”

“That’s like the complete opposite of my job,” Senku says, deadpan. She decides to turn the tables. “What about you?”

“Me?” Gen gives her an almost sheepish grin. “Nothing crazy. I finished school, panicked and then went back. I’m taking classes part-time for now.”

“Still psych?” Gen nods. It’s expected, sure, but Senku always thought—

“I always thought you’d be a performer,” Senku admits.

“I thought you’d be in space by now,” Gen challenges. A wayward piece of hair falls over her eye, and she brushes it away without breaking eye contact.

Senku lets the comment slide. She’s more interested in knowing something else.

“Why’d you choose to come back here?”

Gen tilts her head and scrutinizes Senku. She hesitates, then says, “Would you believe me if I said I was homesick?”

Senku thinks back to the Gen she knew in high school. She’d been fiercely independent, but in an entirely different way than Senku was. Senku was alright all by herself, but equally alright when Byakuya was home. She never felt suffocated. But Gen, back then, had been something like a caged bird. She hid it well, but Senku spent enough time with her to figure it out. Gen was in desperate need of a way out of this town. So, it didn’t come as a surprise when she announced she’d be studying abroad after graduation. 

But then Senku thinks of the Gen who enlisted her in countless schemes to force Taiju and Yuzuriha to confess to each other. Who always neatly placed her shoes right next to Senku’s when visiting her house, and took a moment to memorize the image of their belongings, side by side. Who bought Byakuya a birthday present, when it had slipped even his own daughter’s mind. Who buried her face in Senku’s shoulder to hide the tears in her eyes after her graduation ceremony.

“I’d believe you,” Senku tells her. Gen’s always been more sentimental than she’d like to let on.

Blue eyes bore into Senku’s but she doesn’t budge. Gen searches her face and her countenance goes soft at whatever she finds.

“And what about you?” Gen finally asks. “Why here? There are lots of good schools for physics overseas.”

“This was more convenient. I’m going abroad for my PhD anyway.” 

Gen huffs a little laugh. “Aww, I get it, Senku-chan. I’m sure your father would miss you just as much. You made the right decision for both of you.”

“You’re way off.” She’s hit the nail on the head but Senku would rather die than admit it.

Gen smiles knowingly but doesn’t call her out on the lie. Instead, she leans back in her chair and changes topics.

“So, how are Taiju-chan and Yuzuriha-chan?”

Senku almost winces. She really needs to make plans to catch up with her oldest friends. They’re understanding of how much work she has to do these days, but the longer they go without seeing her, the longer they complain about it the next time they all meet.

“They're good. They got together.”

Gen’s eyes go wide with surprise, then shut in relief. “Oh, thank god. That was always excruciating to watch.” 

Senku concurs. She’d had to put up with it much longer than Gen.

“Who confessed?” Gen asks, with a glint in her eyes that reminds Senku of the girl who’d sit her down at lunch and fill her in on all the gossip she couldn’t care less about. Still, Senku bore with it, if only as a form of recompense for talking Gen’s ear off about quantum dynamics and rocket engines.

“Yuzuriha, obviously,” Senku says.

“I knew I could count on our reliable Yuzuriha-chan.” Then, Gen’s eyes narrow. Senku feels mildly nervous. 

“And what about you, Senku-chan?”

“Huh?”

“Have you met anyone?”

“… No,” Senku says. She thinks back to her brief and uneventful dating history. She’d gone out on a couple dates with a guy in her first year physics class when her friends insisted on it, but ended things as soon as she realized he felt threatened by her higher grades. She’s never tried to pursue anyone, and can’t help but be put off by most people who try to pursue her. 

Whatever happened at her birthday party last year, when Kohaku dragged her to a gay bar, doesn’t count. Senku had been too drunk to remember the details. Just the faint impression of kissing a dark haired woman, with eyes too green to be right.

So, no, Senku has yet to meet anyone. “You know I don’t have time for that kind of thing.”

That was her go-to excuse in high school, when Gen wondered why she never took any confession letters seriously. You’re gorgeous, Senku-chan, she used to say. I feel sorry for your poor admirers.

“You haven’t changed one bit, have you?” Gen teases.

Senku cups her chin in her palm and looks at Gen intently. “I wouldn’t say that.”

Gen’s eyes widen, if only for a brief moment. She swallows, and Senku watches the line of her throat, tracing the pale skin of her neck before it’s swallowed by her turtleneck. Gen’s always worn too many layers. Senku thinks back to high school again, thinks of Gen sprawling across her bed with her long skirt riding up her legs, giving Senku a rare glimpse of her shins. It made an impression.

As if eager for a distraction, Gen reaches across the table and grabs the book Senku had left open next to her laptop. Gen holds it up in the air, scrutinizing the nondescript cover.

“A Relativist’s Toolkit,” Gen reads off. “I wouldn’t want to open this one, right Senku-chan?”

Senku smirks. “Knock yourself out.

Gen starts flipping through the book’s pages, like it’s a magazine and not a miniature textbook. “I have no idea what I’m looking at,” Gen admits, squinting.

“You’re not exactly the target audience for this book. But you know the basics of relativity theory, don’t you?”

“You’re vastly overestimating me. All I can recall is something about a trampoline and a bowling ball.”

Senku wrinkles her nose. “That might be my least favorite analogy of all time.”

“Oh?”

“It’s explaining gravity using gravity. It defeats the purpose.”

Gen tilts her head, smiling again. “So how would you explain it?”

“It’s the geometry that matters,” Senku says. “Everything you think you know about gravity is probably wrong.”

“If you want a visual…” Senku reaches into her pocket and pulls out her phone. It takes her a second to open the album she’s dedicated to student hours.

“Here,” she says, holding up an image she took at the beginning of the semester, of a gray sheet stretched over a protruding funnel, with a piece of green tape running across it.

“You just had that ready?” Gen gapes, then squints at the photo. “What am I even looking at?”

“Space,” Senku says flatly. When Gen continues gawking at her, she sighs, biting back a fond smile. “It’s a sheet, just like your trampoline. Only, it’s curved the other way.”

“Then how does the marble orbit it?”

“Forget the marble. Look at the tape.”

Gen nearly goes cross-eyed trying to focus on the image Senku’s holding up.

“All it shows is that the shortest path between two points isn’t a straight line. It’s curved because the surface is curved. It’s a geodesic.”

“Ah,” Gen says hesitantly. “So it doesn’t matter if it’s curved upward or downward?”

“Exactly. When you factor time into it, things get more complicated.” Senku swipes through a few more images and lands upon a familiar graph. 

“I don’t like the look of that,” Gen says, shuddering.

“It’s straight out of high school physics.”

“I’ve been out of high school for years,” Gen reminds her. Before Senku can tell Gen she’s more than capable of reading a graph, she slides the book back across the table.

“You’ve gotten better at explaining things,” Gen tells her. There’s something warm about the way she’s looking at Senku.

Senku turns her phone off. She can sense that Gen’s more interested in talking to her than receiving an impromptu physics lesson. “I’m a TA. It comes with the job.”

“Oh,” Gen says. “I can definitely see that.”

Senku squints. “You said you were taking classes part-time? Is that all you do?”

“Wouldn’t that be nice?” Gen says wistfully. “No, Senku-chan, I have a job too.”

Senku raises a brow.

“I bartend.”

“Really?”

“Really,” Gen agrees. “I’m liking it so far. It’s entertaining.”

“It must be fun to apply what you’re learning.”

Gen tuts. “It isn’t that easy. People aren’t as categorizable as we like to think.” She glances at Senku’s hot chocolate, and Senku slides it across the table without a second thought.

Gen brings it to her smiling mouth and Senku tries not to stare at where her lips contact the lid. She takes a sip, then says, “I’ve gotten good at telling what drink someone will order based on what they look like, though.”

“Oh, yeah? What do I look like I’d order?”

Gen puts the drink down and takes a moment to think. She props up her chin on her hand and hums.

Then, very seriously, she says, “Something green.”

It’s a cheap joke but Senku laughs. She can’t help it.

“You’ve always been pretty good at reading people, though,” Senku tells her.

Gen’s smile sharpens. “If you say so, Senku-chan.”

Senku-chan. If Gen keeps saying her name over and over, Senku’s gonna start thinking she missed it.

Silence falls over them then. Gen starts fiddling with the napkins lying on the table while Senku takes a moment to refresh her email. It’s properly late now, but her students’ sleeping schedules are worse than her own. For once, she finds her inbox empty.

When she looks up, she finds Gen folding the napkin she’s holding and creasing the corners with her almond shaped fingernails.

Before Senku can ask her what she’s doing, she says, “You know, I saw your name on a paper a while back. It’s a little late now, but—” Gen looks up at her, through silky black lashes, and Senku’s breath catches in her throat “—congratulations.”

The back of Senku’s neck feels hot when she says, “I was one of the last people listed on there. It’s really not that—”

“You’re an undergrad and it wasn’t even in your field. Give yourself more credit.”

Sure, Byakuya, and her friends, and her supervisor already told Senku as much. But hearing it from Gen is different in a way Senku can’t explain. Just— different.

“I’ll be honest… I tried to read it, Senku-chan, I really did.” Gen pouts again, as she shapes the napkin in her hands into a triangle. “I couldn’t make sense of it at all.”

“I wouldn’t expect you to. It’s full of jargon.” In a gentler tone, Senku explains, “I helped improve a mouse model of graft versus host disease. 

But Gen only tilts her head in clear confusion.

“You’ve heard of transplant rejection, haven’t you?”

“Like an organ transplant?”

“Yeah, exactly. If things aren’t properly matched, your immune system registers the new tissue as foreign and attacks it. So, rejection.” Gen nods. 

“Now, graft versus host is when the transplant rejects you.”

“I see… How do you even stop something like that?”

Senku chuckles. “That’s what we’re working on. But really, I didn’t do much. They just had me designing guide RNA.”

She’s met with a blank stare.

“For CRISPR?”

“You’ve lost me again, Senku-chan,” Gen says with a sigh. “All I can recall is a eugenics scandal a few years ago.”

Senku shakes her head, laughing again. “Don’t worry, I wasn’t doing anything that crazy. Just…” Senku trails off as something odd occurs to her. Gen doesn’t strike her as someone who keeps up to date with genetics journals.

“How did you even find it?” Even if the research had somehow made local news, Senku’s name wouldn’t have jumped out.

“Suggested search?” Gen offers weakly.

For Gen to have found a paper like that, she must have been obsessively searching Senku’s name on PubMed or Google Scholar.

“Don’t tell me you…”

Gen reaches for the hot chocolate again. It’s convenient how it hides her face. “I wanted to keep an eye out. Just in case you did something really cool that I could brag about.”

“How would you be bragging?”

“See this incredible scientist right here?” Gen says, voice full of exaggerated wonder. “Well, we went to school together. She was my underclassman. Crazy, isn’t it?”

Senku huffs.

“I taught her how to do her hair,” Gen adds with a wistful little sigh.

It’s all past tense. Of course it is. It doesn’t bother Senku one bit.

“Wait a couple years,” Senku says, ignoring the churning in her stomach at the thought of Gen needing to look her up a few years from now, like Senku really is just a stranger. “I’ll give you something actually worth bragging about.”

“I don’t doubt it.” 

Then Gen’s quiet.

But she still looks expectant. She looks like she wants to say something else, or like she’s waiting for Senku to—

Oh. 

“If you want to know whether I looked you up, the answer is no. I didn’t know where to start.”

Gen looks down at the napkin in her hands. She laughs, but it’s strained. “I didn’t think you’d see through me so easily.”

“It’s only been a few years,” Senku says.

“Four years.”

141,672,221 seconds, Senku thinks. The length doesn’t matter. It doesn’t change–

“It doesn’t change anything.”

“I don’t know. I think it changes some things.” And all of a sudden, the lighthearted atmosphere evaporates, replaced by an air of melancholy Senku’s been desperately trying to avoid. She feels uncomfortable. Something heavy like a stone sits in the pit of her stomach.

“You never gave me your new number,” Senku says.

“You never asked for it.” It isn’t accusatory, but Gen isn’t smiling anymore. 

I didn’t know I should’ve. It’s a weak excuse so Senku doesn’t bother saying it aloud.

“You’ve been here for a year,” she tells Gen instead. “You should’ve at least come to visit.”

“I—”

“If not to see me, then to see Byakuya. He still asks me about you. He misses you.”

“He does?” Gen has no right to sound so surprised. 

“Of course he does.”

“Then maybe I’ll have to stop by some time.” She pushes the hot chocolate back across the table, and Senku takes it without thinking. This back-and-forth feels intentional. If only Senku could decipher Gen’s intentions.

Quieter then, Gen says, “Was he the only one?”

“Huh?”

“Byakuya. Was he the only one who missed me?”

Outside the window, the wind blows fiercely. They aren’t getting out of here anytime soon.

“Course not,” Senku says. Gen’s eyes go soft, and she looks so pleased that Senku can’t help herself. “Taiju did too.”

A pout replaces Gen’s smile, and a drawn out, “Senku-chan,” leaves her mouth, and it strikes Senku, for the nth time this evening, that she’s missed this. Gen’s expression, her voice, her everything.

“I missed you,” Senku tells Gen. “How could I not?”

 Gen’s eyes sparkle. “Good.”

“Good?”

“It’s only fair. Since I missed you too.”

Senku swallows. “How embarrassing,” she mutters.

Gen’s pout returns. “You used to be kinder to me. Am I not your cool upperclassman anymore?”

“You were never cool.”

Gen gasps in mock offense. You used to be kinder, Senku recalls, amused. Gen doesn’t even know the half of it.

Senku used to—

Gen splays her arm across the table then, with a folded napkin sitting in her open palm. Senku looks down and realizes that Gen’s made origami, using napkins instead of square paper. Senku can make out tiny ears and a pointed nose.

“And to think, I worked so hard on this,” Gen complains. 

“For you,” she adds, when Senku continues staring. “A CRISPR mouse, or whatever.”

Senku only blinks. Gen’s holding out a tiny origami animal and Senku’s all but forgotten how to speak.

“They still look like ordinary mice, right?” Gen asks, suddenly concerned.

“Yeah,” Senku breathes. Gen probably expects her to laugh, but any amusement Senku feels has been overshadowed by painful yearning. Her chest feels tight with it. She reaches for the mouse, and feels her mouth shape an incomplete answer. “They still look like…”

Senku takes the craft from Gen’s dainty hand— so unlike Senku’s own —and falters. She should finish the sentence she started. She should say something about mice, or origami, or hell, even physics, but her mind circles back to one sentence, over and over.

It plays on loop. It’s deafening. 

Senku rolls the words around her mouth. She tests their weight. She thinks about saying them. The silence drags on, full of possibility, and Senku considers the chance to get it all off her chest. Nearly five years’ worth of weight, falling away in an instant.

“You know, I—”

“I was in love with you, I think.” Senku only realizes she’s cut Gen off when she looks up to find her gaping. Gen’s mouth is slack and her blue eyes are uncharacteristically open.

“Senku-chan?”

“Back in high school,” Senku clarifies, knowing full well that isn’t what Gen’s asking. “I loved you.”

Gen looks, for lack of a better word, alarmed. Her cheeks are turning pink. She liked to say that Senku’s lack of filter would get her in trouble some day. It seems like that day is today.

“Don’t act like you didn’t know.”

“I… I mean I suspected. But I never—”

“I know,” Senku says, exhaling slowly. The weight is still there, pressing against her rib cage. “You never felt that way about me.”

“No, I— Well, yes, it wasn’t quite like that for me, but that’s not what I mean. I never knew you felt so strongly. I thought it might’ve been a crush.”

It wasn’t like that for m e. It stings. Senku thought she could handle the words, now, four years later, but they leave a bitter taste in her mouth. Even the lukewarm hot chocolate can’t chase it away.

Still, this is one thing Senku refuses to apologize for. “It’s fine. I know you thought of me like a kid sister.” She tries not to grimace at the words.

But Gen shakes her head. “I thought of you like a friend,” she says. “I still do.”

Senku’s silent.

“You don’t understand. You had Taiju-chan and Yuzuriha-chan. You could be friends with anyone you wanted to. People like you, Senku-chan. It’s different for me.”

Senku’s mouth nearly drops open in surprise. “People like you.” Gen’s always been infinitely better at understanding people than Senku is. She had both their teachers and classmates wrapped around her finger. She had Senku, proud, rational Senku, nearly out of her mind.

“It’s different,” Gen insists. “The point is, I was a bit of a loner back then. And being with you was… fun.”

“You’re not alone now.”

“No,” Gen agrees. “But this—” Gen gestures at the origami mouse and Senku’s open textbook still lying on the table “—is still fun.”

Senku nods, satisfied. The weight’s subsiding. It’s a little easier to breathe. “Give me your phone,” she demands.

“What—”

Senku puts out her hand in lieu of an answer. Despite her confusion, Gen does as she’s asked. She unlocks her phone and hands it over.

Senku swipes and silently starts typing, well aware of Gen’s curious gaze. She taps the screen once she’s satisfied, and passes the phone back to Gen.

“There,” she says, as Gen looks down at the updated contact on her phone. “Let me know when you’re not working and want to hang out with me.”

The pink returns to Gen’s face. It suits her. She tucks her hair behind her ear, still staring at Senku’s phone number, and Senku thinks it would be nice to touch it again. 

The sound of her laptop chiming distracts her. Senku shakes off the urge to reach across the table again, and looks at her screen.

As expected, an email from a student awaits her. Senku takes a breath and prepares herself for the inevitable frustration she’ll feel when it becomes abundantly clear that no one thinks to read the syllabus before messaging her.

“Wait, Senku-chan.”

Senku looks away from her laptop to ask Gen what she means, and finds Gen pointing her phone at her face. She taps its screen before Senku even realizes what she’s doing.

“Perfect,” Gen says with a grin. She turns her phone around and displays a photo of Senku in all her disgruntled glory, with her hair spilling out of loosened braids and visible bags under her eyes. A new contact photo.

Senku grimaces. It’s unflattering, but—

“Unless you’d prefer a picture of you in high school.”

But better than the embarrassing high school photos Gen undoubtedly still has in her possession. Senku shakes her head. “Keep the picture. Just send me one of you too.”

She takes a moment to memorize the almost shy smile that graces Gen’s face then, before returning her attention to her responsibilities— which somehow seem less important than they did yesterday.

Throughout the night, their conversation ebbs and flows. Gen relentlessly questions her, like she’s hoping to make up for four years in just one night. Senku tells her about her godawful first year roommate, and the eccentric American scientist who’s agreed to become her PhD supervisor. In return, Gen tells her about the friends she made in university and the manager who was rightfully fired for relentlessly flirting with her.

When Senku’s once again forced to redirect her attention to her laptop, Gen stands and pushes her chair over so she’s sitting right next to Senku, where she can see her screen.

She clicks her tongue and tells Senku to be kinder to her students. “Don’t you want them to write a nice evaluation at the end of the year?”

Senku just pushes her laptop toward her. “By all means, go ahead,” she challenges. It’s definitely against the rules of her contract, but Senku’s too amused by Gen’s attempt at imitating her pattern of speech to care.

“You’re ten billion percent wrong,” Gen narrates as she types. “Are you sure this is the right class for you?”

“I wouldn’t say that.”

“Right. This isn’t the right class for you,” Gen corrects, giggling when Senku snatches her laptop out of her hands.

Still, as time goes on, Gen’s responses become stilted. Not for lack of caring, but because she’s obviously getting tired. Her eyes keep fluttering shut, and Senku can’t help but wonder how she works a night job.

“It’s cold outside,” Gen complains. “It makes me sleepy.”

But when Senku offers her an energy drink, Gen pulls a face. “As a scientist, shouldn’t you know better? That stuff is practically poisonous.”

Senku shrugs. “We’re all hypocrites. I’ll worry about it when I’m fifty.” 

But half an hour later, even Senku, who’s trained herself to stay up obscenely late, feels the consequences of one too many sleepless nights sneaking up on her. She stifles a yawn as she responds to a frantic student who’s somehow missed every deadline outlined in the syllabus.

As she hits send, her laptop warns her it’s on its last life. Senku shuts her laptop and decides to call it a night. She leans back in her chair and stretches, wincing when her back audibly cracks.

She can’t wait to curl up in her bed when she gets home. Unbidden, she wonders what it would be like to have someone there with her. Someone like—

“Senku-chan,” Gen says softly. Senku glances in her direction, and finds Gen resting with her head pillowed in her arms. Her eyes are half-lidded, no doubt heavy with sleep. Still, her voice is clear, almost awed, when she asks, “You were really in love with me?”

Senku stiffens. She thought they’d left that topic behind, but four years have done nothing to dull the edge of Gen’s persistence. Still, unlike Senku, she’s usually more subtle about it.

The question might seem taunting, especially from someone like Gen, but Senku doesn’t sense any malice. Gen’s watching her closely— earnestly.

Senku could play it off now, and spare herself the embarrassment. She could call it a childish infatuation, or an error in her usually impeccable judgment. Senku chooses to do neither. She has a feeling her honesty might prove Gen’s undoing. Senku’s intuition rarely fails her, and right now, it’s telling her Gen brought this topic up again for a reason.

Gen’s never taken compliments well, and Senku intends to exploit that. The thought sends a rush of heat to her face, and has her stomach churning, like the contents of a high school chemistry lab have been emptied inside of her— like calcium carbonate and hydrochloric acid bubbling away, like her very matter’s undergoing a phase change.

Senku hasn’t felt like this in years. She forgot just how vivid her every emotion can feel, how Gen’s very presence sends dopamine coursing through her bloodstream.

“I followed you everywhere,” Senku tells her. “I let you hold my hand. I let you hug me. I don’t even hug my old man.”

And just like Senku expected, Gen swallows. Her eyes flick away, a reaction unnoticeable to anyone but Senku. She’s looking at Senku’s forehead now, instead of her eyes. Senku knows that trick well— Gen taught it to her a long time ago, before Senku knew quite how to charm a crowd full of people. Senku’s nowhere near Gen’s level now, but she’s grown up a little.

Gen’s quiet, despite Senku’s more than sufficient answer. “The big oaf and Yuzuriha teased me about it in front of you,” Senku says in disbelief. “Byakuya too.” What more could Gen possibly need to hear?

Gen bites her lip, trapping it between her teeth and letting it go again. Senku tries and fails to look anywhere else. “And…” Gen starts, pausing deliberately, probably to drive Senku crazy. She raises a brow, prompting Gen to finish the thought.

“What about now?”

Senku blinks. It’s far from the question she expected. Still, it only takes her a second’s consideration to shake her head. “We haven’t spoken in years. We’ve spent more time apart than together.”

Something wilts in Gen’s gaze. They’re her own words. Why does she look so distraught by Senku throwing them back at her?

There’s one perfectly logical explanation. A hypothesis, even. Senku can’t make a conclusion until she’s gathered sufficient data. So, in the interest of science, she finds her gaze flitting to Gen’s arm, splayed out on the table. Her sweater has slid toward her elbow, baring a pale forearm and a birdlike wrist. Senku studies Gen’s slender fingers. Every nail has been neatly painted black. There’s always been something painfully delicate about Gen’s frame, something that has Senku torn between wanting to touch and fearing the very thought. But now, she lets her own hand, all calluses and bluntly cut nails, settle atop of Gen’s.

“But I—” Senku meets Gen’s gaze as she thumbs along the back of Gen’s hand, all the way up to her knuckle. “I don’t dislike you.”

Gen’s quiet wonder makes way for disapproval. “Senku-chan,” she says, flat and unimpressed. The furrow between her brow makes her look more lively, more like the Gen who’d chase her down and chastise her for not sleeping enough. It’s cute.

“Fine.” Senku huffs. Still, she can’t hide the fondness she feels— or ignore the flutter in her stomach. This time, she takes a risk: “I’ll always be a little in love with you. Is that what you wanted to hear?”

Gen’s mouth goes slack. Senku watches in twisted delight, as Gen blinks, trying to take in the words. 

She’s looking somewhere past Senku’s forehead now, maybe trying for her hairline. Her face is turning 1beet red. “I bet you say that to all the girls,” she mumbles. It's the weakest retort Senku’s ever heard from her.

It’s Senku’s turn to be unimpressed. “All zero of them,” she says dryly, rolling her eyes at Gen’s farfetched accusation. There goes her mentalist, asking questions she can’t handle the answers to. “Can’t you just take the compliment?”

Gen shakes her head, almost frustrated. “You’re so…”

“You’re so unfair.”

“Huh?”

“You… you look like that,” Gen says, gesturing in Senku’s general direction, as if that’s supposed to mean anything. “You sound like…” She can’t even finish the thought. This isn’t a Gen that Senku recognizes. It’s exhilarating to see her stumbling over her words, like a fawn on shaky legs. It suits her; her eyes are wide and doe-like, and Senku could choke on the unbridled affection she feels.

“And you have the nerve to tell me you’re in love with me?” Gen says, in that same stunned tone of voice. “It’s unfair.”

“A little in love,” Senku corrects. “And what do you mean, like that?” 

The helplessness leaves Gen’s face. It’s replaced by satisfaction, and as Gen’s eyes narrow, Senku gets the feeling she’s fallen prey to another scheme. Gen had been dangling bait in front of her, and Senku bit down without thinking.

“Well, you’re gorgeous, Senku-chan,” Gen says, low and sincere, and nothing at all like she was back in high school. She isn’t teasing this time. “Hasn’t anyone ever told you?” 

Gen’s looking up at Senku through dark eyelashes, with a playful glimmer in her eyes. There are still traces of red in her ears, and Senku’s certain if she grazed the skin with her fingers, she’d find it searing hot. Gen’s smile is just as warm— soft and pleased and just a little expectant.

Fuck data, Senku thinks. She can’t be blamed for what she does next. 

Senku lowers her head to the table, cupping Gen’s jaw and leaning in close. Gen doesn’t back away, even as her eyes go wide in surprise. Her mouth parts, and it’s the invitation Senku’s been waiting for.

Senku kisses her. 

Gen doesn’t taste like candy floss or strawberries or whatever Senku’s adolescent mind might have dreamt up. She tastes of salt. Her lips are sticky with chapstick, something plain and unassuming. Senku thinks it's cocoa butter. 

Gen’s always had poor circulation and icy hands, but here, she’s warm. She meets Senku’s every press, soft and yielding. She tilts her head, and as soon as Senku wavers, she takes the opportunity to turn the tables.

If Gen’s expecting Senku to stiffen at the press of her tongue, she’s sorely mistaken. Senku slackens her mouth and lets Gen do as she pleases. Senku will take whatever Gen wants to give her. It’s worked that way for years, whether Gen knows it or not.

And, if Senku kisses her deeper, there’s no way Gen won’t know. That’s the approach she’s planning to take anyway. Judging by each curious hum and breathy sigh leaving Gen’s mouth, she has no objections. 

Faintly, Senku wonders if the barista is watching this. She’s probably tarnishing the spotless reputation she’s unintentionally crafted by quietly working here every day— but it’s not like she ever cared about that sort of thing in the first place. Shame isn’t above or beneath her. She simply can’t be bothered.

Ultimately, it’s Gen who breaks the kiss. She tips her head back, and when Senku follows the movement without thinking, Gen’s mouth curves into a grin. Senku’s lips catch the corner of Gen’s as her face turns to the side. Senku isn’t discouraged in the slightest. She presses her lips against the curve of Gen’s jaw and lets the touch linger, before shifting a little right and doing it over again. If Senku has her way, she’ll map out every inch of Gen’s porcelain skin here and now, just like this.

“Senku-chan,” Gen protests, as her hand settles atop of Senku’s head. She doesn't push her away. Senku doesn’t have to look at her to know she’s smiling— she can hear it in Gen’s voice. 

She doesn’t have to look at her, but Senku’s overcome with the urge anyway. She draws back, and finds a sight more than worth it— maybe even worth four years of waiting. Gen’s smile stretches her cheeks and reaches her eyes. It’s the kind of smile she used to hide behind her sleeve, the kind Senku wasn’t sure how to coax out of her. She could have tried harder back then, but Senku thinks it’s better like this. She feels light-headed, but somehow steady on her feet. She can bask in the weightlessness without fearing a bone-crushing fall. Senku isn’t sixteen. She won’t die if she never gets to kiss Gen again, but god, does she want to.

Gen tilts her head.

“Zero girls?” she challenges, while Senku’s still relearning every plane of her face. Senku blinks and finds herself back on solid ground. Way to spoil the moment.

Gen looks far too proud of herself for the quip, smug enough that Senku just has to pull away. To make a point, if nothing else.

Gen doesn’t let her go far. She takes hold of Senku’s face and drags her back in, softly laughing at Senku’s unimpressed frown. It’s laughter at her expense, but Senku can’t bother to take offense, or feel anything other than warm and liquid when faced with the full force of Gen’s mirth. Senku’s thawing like ice under the spring sun, like the snowflakes once caught in Gen’s dark hair— now melted down to nothing. 

“Hey, Senku-chan,” Gen says, once she’s caught her breath. 

Senku hums, all while considering the logistics of inviting Gen over once the storm dies down. It doesn’t have to be for any particular reason. Senku doesn’t expect anything, and wouldn’t want her intentions to be misconstrued, but maybe they could just—

“I’m not in love with you.”

Before Senku has the chance to pull away, before her stomach can even sink, Gen’s leaning in close again. “Not yet.”

Gen’s still cupping her face in her hand, and when her thumb grazes Senku’s cheekbone, Senku feels her mouth go dry. Gen’s eyes are cobalt, lustrous and cool, and they bore into Senku with an intensity bordering on empirical observation. Never before has Senku empathized with the specimens on her microscope slides. She wonders if Gen can read every sappy thought she’s had, like the remnants are somehow written across her face.

Gen’s been looking at her all night. But now, Senku feels seen. Her cheeks are burning, as blood rushes to her face without her permission.

This time, Gen’s smile is wickedly satisfied. “But you’re making a convincing case,” she tells Senku.

Senku swallows and reminds herself of the disappointment in Gen’s eyes only a few moments earlier, when Senku reminded her that they haven’t spoken in years. This is just Gen doing what she does best— putting on a show. All this misdirection serves to help her save face. All so she can pretend she has the upper hand.

She’s ridiculous. Senku missed her.

That doesn’t mean she’ll let her win.

“You’re stuck with me for another—” Senku glances out the window and makes a logical inference “—two hours.” Her voice comes out steadier than she expected. “You’ll eat your words,” Senku promises, low and dark, like she’s making a threat.

Gen laughs, bell-like. “Love isn’t a science, my dear.” She wields the endearment like a weapon. Senku, who’s been starved of the sound of dear on Gen’s lips, is almost foolish enough to fall for it. 

“There isn’t a formula and there are certainly no guarantees,” Gen explains. It doesn’t sound like she’s making an excuse. If anything, Gen’s conducting a test. An experiment of her own.

Senku tuts. “I don’t know what kind of pseudoscience they’re teaching you psych grads. There aren’t any guarantees in science.”

Senku lowers her gaze. Gen’s worrying her lip with her teeth again, but Senku won’t lose her train of thought so easily. Even if Gen’s lips are still shining with smudged chapstick under the warm ceiling lights, and Senku wants nothing more than to just—

“It’s always a risk,” Senku says plainly. “Sometimes you end up nowhere. But sometimes…”

Senku looks up then, meeting Gen’s inquisitive stare. “Sometimes you find something incredible.”

“What kind of incredible things are you hoping to discover, Senku-sensei?” Gen teases. “A new planet? A new galaxy?”

Senku watches Gen blink, paying utmost concentration to each flutter of dark lashes. There are stars in her blue eyes.

“Sure. Something like that.”

When Gen’s breath hitches, Senku knows she’s been understood. How’s that for making a convincing case? 

If Gen closes the distance this time, if Senku threads her fingers through two-toned hair, if Gen says something quiet and sweet and unflinchingly honest against Senku’s mouth— it’s really no one’s business but their own. The spiraling snow casts a veil around this tiny cafe, sheltering Senku and Gen and four years’ worth of suspended dreams. They’re dreams Senku intends to see come to fruition.

They’re dreams that’ll outlive the night. 

When morning arrives, Senku will find the streets swathed in snow. Asagiri Gen, with Senku’s green scarf draped around her neck, will offer her a frigid hand. And when Senku takes it and warms it between her own, she’ll realize that, sometimes, dreams pale in comparison.