Archive of Our Own

Yuzuriha + Taiju 

Senku always found solace in stargazing. Ever since he began to question the universe that very day to his father, the stars above, in his opinion, are one of the most mesmerizing creations of them all. To think mere balls of hydrogen and helium could form such a beautiful creation was beyond him. They helped his overactive brain slow down, something that almost never happens. 

It was a hassle to find a proper place to stargaze in the modern world, and you could thank light pollution for that. But after being freed from petrification 3700 years later, the sea of illuminated sparks in the dark sky had never been so clear. All he had to do was look up at night and feel his chest lighten at the sight of one of science’s greatest beauties. 

Despite being on the run from Tsukasa, and the fact that rest is important, he just had to catch a glimpse of the sky. It’s not like his brain was planning on letting him sleep any time sooner. 

So he slips out of his sleeping bag and heads to the open to do what he always does in these situations. He sits down in a swift drop and kicks his legs over the edge of the cliff, letting the breeze brush through his upright hair. 

The stars are as bright as ever; clearer than he’s ever seen in a while. Sure he used to climb out into the wilderness with his old man, but it could never beat such a breathtaking sight free from all sorts of pollution. 

Senku would be lying if he were to deny the fact he’s thought of finding some way to avoid hiding the stars once more through the reestablishment of civilization. 

The campfire crackles in the distance, and Taiju’s dad-like snoring is faint from where he sleeps. 

Looking at the pool of stars always draws out the emotions that are usually constipated within. As much as it was a mess, it also brought peace to him. 

His eyes could truly get lost in that ocean of a galaxy before him. 

The light crunch of dirt is caught by his hearing, but Senku doesn’t budge. It’s quite obvious it isn’t Tsukasa after all. 

Yuzuriha settles next to her quiet friend wordlessly and follows his crimson gaze to the sky above. 

“Can’t sleep, huh?” She inquires after the silence stretches out. 

Senku tilts his head, attention glued to the sky. 

“Guess you could say that.” He responds, strands dancing with the delicate wind. He always wishes he could freeze time, even if scientifically impossible (for now), and cherish every second.

“I never knew nighttime could look so pretty.” Yuzuriha admits once she brings her knees to her chest so she could prop her chin in between them. 

“The modern world unfortunately hid that behind neon lights and all that nonsense of entertainment.” Senku states, stretching his arms backwards and splaying his fingers so he could lean back. 

“Makes sense why you were always trying to find the less illuminated places to get a better view with your telescope.” The brunette laughs a little, lashes lowering. 

“No need for any of that anymore.” Senku says with the lazy roll of his shoulders.

“Good point.” 

They fall silent for a beat, and Senku’s red eyes flick sideways just in time to catch Yuzuriha’s saddened look. 

He doesn’t comment or press her for it, knowing it is linked with reminiscing the past. He doesn’t blame her. He also misses the internet, books, his mentor, his science equipment, dreaming about going to space, the science club, and his old man. Heck he even missed school. 

“You think we can really bring humanity and the world back the way it was?” She finds herself wondering aloud bitterly. 

“Ten billion percent.” Senku answers without missing a beat.

Yuzuriha finally meets his gaze slowly, questions glistening in her dark eyes. 

“How?” 

“How what? How are we going to do it? That’s quite the lecture you’re asking from me, you know.” The teen deadpans.

That draws a small laugh from his fellow friend. 

“No no it’s just…” her smile fades slowly, “how are you so sure….?” 

Senku’s lip purses slightly as he mulls over it. His answer for it is quite childish, and he’s pretty sure there’s no other way to make it sound more mature. 

He rubs at his temple momentarily before switching his posture into a cross-legged one. 

“Guess it’s just because I want it. I want it to happen, I mean. And the fact that we quite literally have to speedrun the evolution of humanity is pretty exhilarating. But to say it as a way of reassurance or some crappy motivational speech is… something I don’t think I can do.” Senku finds himself admitting. 

Stargazing also made him noticeably more honest about his emotions. Plus, sugarcoating their current situation is beyond pointless. 

Yuzuriha’s eyes trail up to the sky once more thoughtfully.

“Nah. I think hearing you say it in such a… you way is reassuring enough.” She replies with a small smile.

“Thanks I guess.”

“No… really. I’m glad you and Taiju are here with me. It motivates me that the people I care about are alive, depetrified and by my side.” Yuzuriha says a bit more firmly, grabbing Senku’s attention with the switch in her tone. 

“…oh.” Is what leaves his lips awkwardly. 

Unsure of what to say, his eyes flick to the stars above as his brain tries to scrape up something for him to say. 

So instead, he finds himself asking:

“You know your constellations, right?”

Yuzuriha blinks in slight surprise at the switch-up before nodding slowly; this is Senku after all.

“Yeah… kind of? I guess I read about them in middle school when I had a zodiac sign phase. Why?” 

“Well constellations move. Not that it’s obvious to the human eye and all, but they do, since the stars shift positions, also known as proper motion. So as of now, the constellations we used to know in our time probably look a bit different now, but that’s just because their placement shifted.” Senku rambles without a singular pause or blink, which is complimented with aggressive gestures. 

“Really?” The brunette pipes up as she processes the information, “that’s… woah.”

“I know right? Pretty sick if you ask me. I can actually point out a few of them and compare them with the way they used to look.” 

Yuzuriha’s eyes crinkle.

“That would be lovely. We should wake up Taiju so he doesn’t miss out.” 

Senku shoots a quick glance at the said boy snoring in the distance under a tree.

“Nah. As much as it would be nice to have his company, that big oaf needs to rest up for tomorrow. He might not show it all the time, but even someone with inhumane strength like him gets exhausted.” The young boy states with a small scratch to his chin. 

“I see…” Yuzuriha murmurs as her own attention shifts to Taiju in the difference. 

Senku waits for her to decide to move on as facts start to pile up in his mind to the point he could almost see the text. Heck, he thinks he can even taste them from how much he wanted to share them. 

“Uh.. I think we should wake him up.” Yuzuriha declares as she stands up. 

“Hah? Why? I thought you—”

“If we don’t he’s going to roll into the campfire.” She interrupts gravely. In any other circumstance Senku would have burst out laughing at such stupidity coming from Taiju as per usual. However at this hour and during their current flee from Tsukasa, having Taiju turn into toast was the last thing they needed.

“I think his sleeping bag is setting on fire!” Yuzuriha exclaims and starts to rush off. 

Senku groans and stumbles after her. Typical Taiju. 

Guess the rest of these facts swarming in his ears have to wait for another day. 

Kohaku 

“You’re weird.” Kohaku states quite bluntly when she finds Senku sitting up in a tree. She truly did wonder how someone as scrawny as that idiot managed to get up there until she noticed a weird contraption next to the tree on the ground. 

“Hm?” Senku responds, uncaring of how rude her comment came off as.

“You’re weird.” She repeats.

“Yeah, no shit. I heard you the first time.” Senku deadpans as red eyes look over his shoulder, “I let out that noise expecting you to elaborate.”

The blonde scoffs as she seats herself on the branch above. 

“How was I supposed to know?”

“Social cues. Duh.”

“Look who’s talking.”

“Shut up.” 

Kohaku can’t stop the cocky smirk of amusement from tugging at her face before it forms. Senku even mirrors her amusement with a small snort. 

A pause.

“No but seriously. What’s with you and looking at the sky all the time? Kinda weird if you ask me.” The blonde inquires more seriously this time.

Senku quirks an eyebrow at that. 

“Why’s looking at the stars weird?” He asks back.

“You mean those glowing specks in the sky? Cuz they’re just glowing specks.” Kohaku responds quite dryly. 

Senku’s eye twitches at that, expression irking. 

“Damn, what’s up with that look?” She questions airily. 

The boy scowls deeply as if it were truly a grave matter. 

“I find it kinda stupid you’re saying such things when you’ve got some crazy eyesight.” He drawls. 

“I’m just speaking what’s on my mind, though.” 

Senku glances up at her from his lower branch, somewhat disgruntled. 

Kohaku’s got such good eyesight yet she’s never bothered admiring the night sky with them?!

Quite ridiculous in his opinion. 

“Have you ever taken time to admire your surroundings when you’re bored or stressed?” He asks her simply. 

Kohaku cocks her head like a hawk. 

“Obviously. Who doesn’t?” 

Crazy confidence for someone dense enough to not explore the wonders of the universe. He thinks sourly while jabbing his pinky into his ear momentarily.

Senku sighs heavily and kicks his dangling legs. That creates a bit of motion to rattle through the branch below him. 

“Look up at the sky.” He instructs.

Kohaku sighs. 

“Why?” 

“Just do it.” 

She rolls her sparkling blue eyes before staring at the starry night sky. There quite literally is no point in any of this, and just watching the stars sparkle makes her grow impatient. 

“Can I look away now?” 

“No.” 

“But—”

“Look properly. Trust me.” Senku cuts in, treating it like an urgent matter. It was pretty clear that anything that had to do with the sky above was personal, and Kohaku didn’t blame him. She’d probably feel the same way too if someone undermined something she adored. 

So she chooses to listen with a small exhale, keen eyes reflecting the dazzling moonlight. 

Kohaku could look at the moon and its intricate details for hours, but she couldn’t say the same about stars. 

They were just glowing balls in the sky, right?

Wrong.

Kohaku wonders why she’s never bothered to properly pay attention to the night sky before. 

Because once she listens, it’s as if she can see their true forms. Each dot in the sky had its own unique color: ranging from soft yellow to ominous blue to raging red. Even so, they all shine in a way that resonates with her soul. 

“Why do they shine so…?” She breathes out. 

Senku smiles giddily and comically straightens as he launches into an explanation. 

“Well, you know how you’re seeing a few stars changing their colors? It’s actually Earth’s atmosphere playing tricks on us. For instance, atmospheric turbulence is where the air around us moves in different layers, temperatures and densities. So when that very starlight you’re seeing passes through these layers, they bend in different ways to cause an illusion of sorts.” He rambles excitedly, even if Kohaku was too distracted by the beautiful sight her eyes take in. 

Despite most terms sounding like nonsense, she still wants to listen. Learn. Understand these specks she used to think were nothing but decorations littering the sky. 

“Hey, Kohaku. Get your ass down here. I wanna show you something cool.“ Senku then declares with the tilt of his head.

“You can tell me whatever you want from where you are. This view is perfect. I’m not moving.”

Senku narrows his eyes and flicks a bramble at her. She doesn’t budge. 

Guess her eyes are showing her a true haven. 

He’s a bit jealous of her visual capabilities to be honest. 

“Alright, fine. So you’re going to want to look for Orion’s Belt.”

“Who the hell is Orion? Why am I looking for someone’s belt?” Kohaku exclaims, bewildered by such a statement that it makes her look away.

Senku suppresses a groan and instead rolls his eyes. 

“He’s not a person! Rather… a guy from like… myths and stories… whatever, that’s just going to make me go off track. Just look for three bright stars in a short, straight line. Tell me when you see them.” 

Kohaku’s lashes flutter as she ponders over such weird instructions before obliging. She skims the sea of magical specks, hunting for the requirement until she indeed notices the odd batch of stars.  

“Found them. Now what?” The blonde asks. 

“Imagine the rest of him. For instance, the belt is technically his waist, so logically the two stars above are his shoulders and the two below are his legs and feet.” Senku states as he points at the sky from where he’s seated underneath. He’s practically got it memorized. Sure Orion’s placement is a bit different than 3700 years prior to petrification, but nothing else thankfully changed. 

He watches the gears turn behind Kohaku’s ocean blue eyes, her brows dipping in thought as she pieces Orion together. 

“Why is his top left shoulder reddish?” She inquires with a minor squint. 

Kudos to Kohaku and her mind-blowing eyesight for noticing such a thing so quickly. 

“You found it. That’s exactly what I wanted to show you.” Senku states with the sharp jab of this finger, “I’m impressed, but expect no less from those eyes of yours.” 

He crosses his legs over one another before he continues. 

“That’s Betelgeuse. An iconic star, if you ask me. It’s about 700 times the size of our Sun.” 

“What?!” Kohaku shrieks, stunned by such information, “but why compare it to our Sun?”

Senku grins broadly.

“‘Cuz the sun’s a star, Kohaku.”

If getting your mind blown was physically possible, he’s pretty sure he can see it happening to Kohaku. It makes him more eager to indulge in the life-cycle of stars. Sure he might scare her a little, but that’s the truth and nature of the world after all.

Much to his delight, Senku is given the opportunity to ramble the whole night about space and its precious stars. He isn’t even sure when he falls asleep in the trees with Kohaku, but he’s pretty damned satisfied. 

That’s until Chrome finds them and wakes them up with whines about how he missed out on some “bad science”, insisting that Senku should tell him these kinds of things too. Obviously they have other things they need to do, so Senku has to forcefully push aside the topic for later despite the urge to rant. Kohaku takes it as her chance to brag and poke at a grouchy Chrome.

Even if they’re currently piled with work, Senku does plan on making some time to give Chrome a turn so he’s given the chance to gush about the night sky. 

He can’t help it after all.

Suika

Senku was busy wandering around the forest, originally scavenging for materials that would be easier to spot at night but obviously getting distracted by the dark, illuminated sky. 

He passes by a tree into the flower field, and he swears the ground was smooth. Was smooth, because he straight up rams his foot into something hard.

“Ow! Shit!” He exclaims and hops around a bit on one foot with clenched teeth. 

Whatever he hit grew a body and began to apologize hastily for the caused pain. 

Senku almost believes it was some form of unknown sleep deprivation catching up to him until he realizes who it is.

“Suika?” He tests out slowly. 

The young melon girl nods. 

“Yeah..?”

“Damn, you scared me.” He confesses and pinches the bridge of his nose. He then pauses. Furrows his eyebrows. 

“What’re you doing up so late?” Senku interrogates, curious as to why the little girl was roaming around at such a late hour.

Suika fidgets timidly. 

“I couldn’t sleep.” She admits softly. 

Senku softens ever so slightly, but it’s not like someone as young as Suika would notice. 

“So why are you out here?” He prompts further. 

“I thought picking flowers might help.” She states, wringing her fingers together meekly as if she was doing something ridiculous. 

“I see. Say, I think I’d like to pick some flowers with you.” 

“Really?” She squeaks a bit hopefully. 

“Really.” Senku confirms. 

Suika beams and latches onto his clothes. He doesn’t really mind, instead allowing her to guide them into a more clear area that has a better view of the stars. The pair wander around the field of flowers, the batch of colors painted a delicate hue of soft blue. 

“What are we looking for specifically?” Senku asks, hands on his hips. 

“White flowers. I’m trying to collect as many different types as I can.” Suika answers as she already gets to work, clearly spotting a few. 

“Whatever you say, boss.” Senku salutes, making Suika giggle as he roams about in search of what she likes. They do come across a handful of variants of white flowers through diligent searching, and gather them in a makeshift bouquet made by none other than Suika herself. 

Senku also takes it as a chance to throw in a few facts about each flower they pick, and it clearly delights the young girl. 

“Why get those ones? They’re closed…” She frowns as he hands over a handful of daisies. 

“Well, Bellis perennis, better known as daisies, actually close their petals at night and open them in the morning. It’s why they’re used as a symbol of purity and innocence.”

“Woah…”

“I know, right?”

Once they are sure there are no more breeds of white flowers, the duo settle down in the flower field, Suika on her knees and Senku cross-legged. The sea of beauty above catches their gazes instantly like moths attracted to light. 

“Ever wondered what’s out there, Suika?” Senku questions after a long moment of silence as the little girl admires the sight before her. 

“There’s more out there?” She gapes innocently, curiosity oozing from her tone.

“Sure is. Scientists believe there could be other people living on other planets just like this one.“

“Woah… so there’s more beyond the stars?”

”You know what they are? You get ten billion points for that.”

Suika smiles proudly at herself for the praise. 

“Kohaku told me about them the other day. I think they’re very pretty.” She declares with pride. 

Senku hums. 

“I agree with you. They really are something else.” 

Suika fiddles around with a few flowers as she gathers the courage to request, “say… Can you tell me more about them?”

Senku suppresses a childish beam. 

“I don’t see why not. Alright… you know how babies get born in their mothers’ womb, or rather, their bellies? Well it’s the same for stars.” He states with the jab of his finger. 

Suika blinks. 

“So stars have mommies?” She interprets. 

Senku snickers. 

“Guess you could say that. Stars sometimes can be born inside nebulae. They’re giant clouds of gas and dust that look like a nursery but for the cosmics.” 

“What’s cosmics?”

“It’s a way of referring to the universe outside of Earth.”

Suika nods, clearly digesting the information being handed to her with caution. 

“Why do some stars make shapes?” She moves on after gazing up at the sky for a few minutes. 

“Those are constellations. They played an important role back then for myths and beliefs. They can look like people or animals. For instance, see that thing that looks like a ladle?” 

Suika uses her helmet to get a better view at where Senku points. 

“I think so…”

Senku makes sure she can actually see it before continuing, “that’s Ursa Major, also known as the Great Bear.”

“A bear?!” Suika echoes. 

“You got it. There’s also a scorpion called Scorpius and a lion called Leo.”

“A lion?! Wowie!” She squeaks in awe, “are there more animals?!”

Senku laughs, eyes glinting in excitement.  

“Of course there are! See, there’s Delphinus, a dolphin, and you could easily spot it by…”

Senku goes on and on about the different animal-like constellations for Suika’s sake, to which delights her greatly. He even goes as far as to tell her the stories behind each one, their benefits, and when you can see them the best. 

Seeing such childish interest and joy in Suika, even if she was slowly descending into sleepiness, reminds him of himself back in the modern world. The curiosity, the never ending questions, it was enjoyable to see.

Eventually, however, he has to cut his information spouting short when Suika’s lulling head finally droops and she dozes off. She flops a bit onto Senku, her little helmet safe on the bed of flowers. The contact makes him tense up from its abruptness, yet Senku doesn’t really try to nudge her off. Instead, he fixes their position into something more comfortable so she sleeps well.

If modern him saw this, he probably would have freaked out and thought the current Senku lost his mind.

He crosses his arms behind his head and watches the stars twinkling above with a small exhale, Suika curled up against his side.   

I’m getting too soft for my own good.

Chrome

Chrome was, least to say, an awful roommate. No hard feelings. But it’s almost impossible to sleep near that guy without getting kicked in the head or waking up near the damn window. Even if you slept on the other side of the room, Chrome would still somehow find a way to end up on top of you. He sleep-talked and sleep-walked and sleep-fought and just did everything that was considered annoying while unconscious. 

A restless sleeper, unfortunately.

Senku sometimes wonders how he even manages to sleep in the same room as this idiot.  

Tonight was one of those Chrome-nights where Chrome did the Chrome things in his sleep that drove Senku insane. 

Usually Senku would just walk out if he felt like it and sleep in the lab for the rest of the night, but for some reason he just feels compelled to not do that this time. 

Because getting kicked in the head for the third time can only take one’s patience so far. 

He grabs the boy’s leg the next time it almost hits him and yanks him the hardest he can. 

Chrome wakes up almost instantly with a shriek as he gets dragged around. 

“What the—?! Hey! Lemme go! You woke me up at the best part of my dream!” He cries and starts squirming around. 

“Let me guess: you finally confessing your feelings to Ruri and kissing her.“ Senku deadpans amidst the whines of complaint. 

Chrome’s cheeks color once his brain fully processes the comment.

“Don’t try suggesting stuff like that!” He squawks and writhes in an attempt to free himself from the agitated teen’s grip. 

“Then why are you always acting like you’re Jackie Chan in your damned sleep?!” 

Chrome blinks as Senku finally lets him go. 

“Who’s Jackie Chan?” He questions like it’s the most important piece of information given to him. 

Senku nearly facepalms himself at Chrome’s antics. Seriously, this kid was weirdly stupid and only smart when you needed him to be.

“Never mind that! Why’re you such a restless sleeper?!” 

Chrome stares. Then a sheepish smile breaks across his face.

“Ohhh… uh… sorry?”  

Senku scowls. 

“Hey! It’s not like I can control it or anything!” The boy tries to defend himself rapidly. 

Red eyes narrow sharply. 

"Can't you learn how to limit it or something…?” He requests as if it was the easiest thing in the world. 

“Like hell I can! If that were possible, then I would have done it ages ago.” He huffs and sits up in one wobbly motion, arms crossed tightly over his chest as he bristles. 

Senku rolls his eyes and looks over Chrome, his eyes burning from the lack of sleep uncomfortably. 

“Why does it happen anyway?” He then prompts on more gently. 

Chrome scratches the back of his head as he mulls over a proper answer to give. Yet there truly was no other way to put it but confess. 

“I guess it just happens whenever I’m excited..? I don’t really know how to explain it to be honest… but whenever I know I get to explore or that there’s more science stuff I can learn I get all restless and don’t even realize it.” 

Senku nods, mind easily weaving up a solution to this situation.

“So if I tell you a few facts, will that calm your body from doing gymnastics in your sleep?” 

“Huh?” 

Senku doesn’t bother with elaborating, instead points to the window before striding off to it and propping his elbows on the ledge. 

Cryptic. Chrome thinks with the twist of his expression, but slowly drags himself to his feet and follows. He stands awkwardly next to Senku, back in a small slouch as he tries to mimic gazing up into the sky. 

“Why are we doing this again?” Chrome can’t help but wonder aloud. 

“Why not? Looking at the stars is calming, is it not?” Senku retorts quietly, cheek smushed against his hand. 

The younger boy shuffles slightly. 

“I mean… I guess so.” But where’s the science facts I was promised?

Senku clearly caught the sulk that spread on Chrome’s face before signing and muttering something about impatience. 

“You see the way the stars are ordered? Almost like they’re not randomly placed.” He starts, expression tender. 

“You mean the constellations?” 

“Correct. They’re quite useful for traveling and knowing where you are.” 

“Oh.. like the North Star you mentioned before?” Chrome recalls, “so that’s why you were pretty stunned to know it changed…” 

“Mhm. Precession messes with them since Earth wobbles like a spinning top. Nevertheless, they remain the same. It’s just their placement that changes. For instance, the Zodiac has also shifted since then.”

Chrome squints at the sky above, hoping he could spot whatever Senku’s talking about. 

“What’re the Zodiac?”

Senku glances over momentarily before returning to the sky. 

“They’re twelve constellations. Official ones, at the very least, that lie along the Sun’s yearly path.”

“Yearly path…?” The boy echoes. 

“When the Earth orbits the Sun, it sort of looks like the Sun is moving through the stars during the year. The path it looks like it’s followed is the ecliptic, which is basically a perfect circle around the sky. So the constellations on the path are the Zodiacs… you know, Aries, Libra, Gemini, and whatever. Can’t understand why it became some weird trend for people in the modern world…” Senku mutters with a twitching brow at the recollection. 

“What’s a trend?” 

“You really don’t want to know.” 

Chrome doesn’t comment on the agitated expression on Senku’s face. 

Is it really that bad…? 

“Anyway. Did you know constellations really aren’t groups?”

“Wait… seriously? But don’t people refer to them as that though?” 

Senku can’t help but grin as he launches into his next rant. 

“Well, yeah. That’s just to make it easier for people to visualize. In reality, the stars in a constellation really have nothing to do with each other at all. They just look close together from where we stand, but some are hundreds of light-years apart.” 

“Are light-years long?” Chrome questions. 

“Hell yeah they are. One light-year is approximately 9460730472580800 meters.” He calculates instantly. 

Chrome stares. Blinks. 

Wait what did he just say…? His brain spouts as it couldn’t keep up with whatever value had been stated. 

“That’s um… a lot of numbers.” Chrome chooses to say slowly.  

“Totally. And funny enough, some constellations hide crazy deep-sky objects! Take Virgo, for instance, which has the Virgo Cluster that contains thousands of galaxies.” 

“When you say galaxies, you mean…?” 

“Solar systems just like ours.” Senku supplies. 

“Woah… that’s-that’s totally bad!” Chrome squawks, eyes sparkling with wonder, “Tell me more! Please!”

Senku’s brows crease slightly. 

“What happened to putting you to sleep?” 

The younger teen grows bashful as his face pinches into a pout. 

“Come on! Why sleep now when I can learn some badass stuff about the stars?!” He whines.

“‘Cuz we’ve got a shit ton of work to do tomorrow.” Senku deadpans in a way that draws out a groan. 

“Just this time. Pleeeaaaase! Think about it! You can rant as much as you want and I’ll enjoy every bit!”

Quite tempting. But the cons outweigh the pros. Exhaustion will jumble up our brains and lethargy will increase, decreasing production rate. Senku thinks, eyes watching the squirming teen before him trying to convince him with puppy eyes of all things. 

Crimson red shifts to the starry sky and reflects the wondrous shine of the mysterious night. 

He sighs, hands propped on his hips.

“Alright, fine.” 

Chrome celebrates to himself and straightens his posture, brown eyes twinkling in anticipation. 

Sleep can wait another night, I suppose.

Senku then launches into a series of rambles, knowing damn well they weren’t going to get anything done the next day.

And man was he right.

Ruri

She couldn’t deny she was quite worried about Senku after they found out his father was dead. 

The way he just… managed to stop crying in an instant was concerningly eerie. 

So Ruri finds herself leaving her bed one evening and taking a late-night stroll. 

She’s sure Senku is awake. He always is. Whether it was a project or just wanting some alone time, he was out at night. 

It makes her wonder if he even actually takes time for himself to sleep. 

Ruri’s legs guide her gracefully, blonde hair swaying behind her elegantly. 

Surely enough, she finds the young boy roaming around his father’s grave, head tilted up to the sky. 

His expression is unreadable, but his eyes are clearly packed with emotions that were never spoken. 

“Good evening.” Ruri murmurs in a tender manner to announce her presence. She’s pretty sure he already knew she was there. 

“Evening.” Senku returns, gaze unmoving. 

Ruri blinks silently and stands next to his tense figure, clasping her hands behind her back. 

“What brings you here?” The teenager then inquires.

“Just wanted to free my mind a bit. A midnight stroll does wonders.” Ruri answers. She keeps her gaze trailed onto the sky, just like him, so as to not bother him any further. 

She already knew he hated expressing himself normally, and didn’t want to bring any further discomfort to him. 

“Yeah. Can totally relate.” Senku mutters. He doesn’t launch into any scientific rants about the pros and cons of what she stated she was doing. 

He’s just… quiet. 

Then:

“I know you’re worried.” 

“..of course I am. Why wouldn’t I be?” Ruri tilts her head, then chooses to throw in, “I’m your ex-wife, after all.”

Senku snorts at that, lips quirking slightly in amusement. 

Score. 

“Only for a freaking minute, you know.” He deadpans. 

Ruri smiles softly. 

“Still counts.” 

Then silence. 

Ruri allows her long hair to brush against her skin and tucks a few strands behind her ear. 

“I used to spend my nights looking at the sky. Back when I was sick, I mean.” She whispers.

Senku pauses and glances, finally breaking contact with the sky before them. 

“The stars were always beautiful. Even if I was on the brink of death, they always made me feel at peace.” Ruri continues solemnly, “I sometimes prayed to them hoping that whatever is out there could help me and Kohaku.”

A beat. 

“And then the universe brought you to us.”

Senku feels a faint tingle in the back of his head; a tug in his chest. 

He forces himself to return to the sea of stars, because damn he hated how vulnerable he was feeling right now. 

“You’re too pure for your own good.” Is what he musters instead with a shifting gaze. 

Ruri hums. 

“You’re just saying that to push me away.”

“Maybe. I dunno.”

The blonde shifts her doe eyes to his profile.

“Tell me about him.”

Senku debates it wordlessly. He’s pretty sure if he says too much he might choke on his own words and start sobbing like some 5 year old. Yet at the same time if he stays quiet that would be plain rude and probably would make Ruri worry even further. 

So he settles on trying. 

Trying. 

“He was… an idiot.” He starts slowly, and it instantly triggers a wave of memories with Byakuya. Damn he can feel his throat lump instantly and his eyes burning. 

“An idiot?” Ruri echoes. 

“Yeah. Not in.. I don’t mean it in a bad way. He was just… a lot. He took me in. Always made time for me. Made sure I didn’t starve myself to death when I was deathly focused on a new project.” A shaky inhale, “he sold his own damned car just to get me a shit ton of science equipment.”

Ruri only listens and nods her head a few times. She doesn’t say anything that might make it awkward or let Senku clam up in an instant. It’s refreshing, to be honest. 

“That old man really wanted to become an astronaut even if he knew the requirements were a bit ridiculous for his old ass. Even so he tried, and I couldn’t help but do my own things to help him. And it worked in the end.”

Senku’s really trying not to break down at the moment. In front of Ruri again would just be embarrassing. 

“You know.. that dumbass wanted to eat ramen in space.”

“As in the food you made for the village?”

“Yeah. And it’s quite difficult to turn it into space food. But I still tried, you know? And with enough trial and error, I succeeded.”

The stars reflected and shone in Senku’s glistening eyes. The muscles in his face are tense, and he refuses to look back down to Ruri. 

She doesn’t lecture him about how suppressing emotions isn’t healthy. She doesn’t start freaking out or look at him like he’s some stranger to her. 

She just stands next to his side as some form of an anchor for his sake. 

“That old man… no… my dad.. was an idiot.” It stings to use verbs in the past tense, “and he was stupidly selfless and idiotically too caring for his own damn good. And I—” 

His voice breaks and draws out internal curses from him as he ducks his head. 

I never thanked him properly for any of it. 

I wish I had more time. 

I miss him for fuck’s sake. 

I hate the universe for taking him away from me. 

He can already feel the warm of saline tears slide down his cheeks before he can stop it this time. 

“Ah… shit.” 

Senku hastily tries to scrub them away, but they won’t stop like the pain in the ass they are. 

Ruri watches his external struggle. She doesn’t judge. She doesn’t make it awkward. She doesn’t start invading his personal space. She just interlaces her fingers before her and watches with tender eyes. 

“It’s okay to grieve, Senku.” She whispers.

Such simple words bash through the dam in such a way that sucks the air out of his lungs and lets tears shower the ground beneath him. 

He really shouldn’t show weakness, he knows it.

But he just can’t help it sometimes. 

So he cries silently.

Senku has always been a silent crier. He got judged for it a lot too. It sometimes even freaked out Byakuya. 

Ruri merely watches the sky above with her tender eyes, an anchor for his current state. She really was too damned kind for her own good. Her presence screamed warmth and comfort, and she didn’t inch into his personal space to provide such a thing.

And it’s all he really needed as he let his tears speak for his emotions.

Gen

The telescope creaks slightly as Senku adjusts it with care. The makeshift observatory was and is probably the best thing that has ever happened to him since he broke free from the stone. 

Scratch out probably; it is definitely the best thing that has happened so far. 

Sure it was a bit far from the normal telescopes in the modern world— but to be able to gape at the sky up close is something that makes him want to cherish such a birthday gift. 

It makes him feel like he’s a little kid again: no pressure weighing his thoughts down. 

The familiar faint sound of a tray being placed on the floor is caught by his ears.

He doesn’t budge from where he sits; he knows damn well who it is. 

“I haven’t seen you wandering around much at night ever since you got this observatory for your birthday. I’m flattered you enjoy my gift that much, Senku-chan.” 

Senku rolls his eyes.

“Good evening to you too, mentalist. And it’s quite flawed if you ask me, so don’t let your ego loose. I can almost taste it.” He mutters, the light scent of flowers making his nose scrunch. 

Gen settles next to him with a sigh. 

“Ouch! How rude of you, Senku-chan! You’ve wounded my poor heart!”

“You’ll live.” 

He hears Gen snort at the comment, and he can’t help but let his lips curve upwards in amusement. 

The older male settles next to him, the layers of clothes he wears rubbing against each other to produce a soft sound. Senku wonders how he even breathes with that many layers of clothing. 

Oh well. 

He hears the tray scrape against the floor as it’s nudged close to him. Senku reaches down for his cup of tea without breaking eye contact with the sky. He’s practically memorized the precise location in which Gen puts the tray due to this becoming a long-stretched routine.  

“It gets awfully cold at night. I’m glad the weather’s beginning to warm up.” Gen states as he splays his fingers around his own warm cup.

Senku glances at him for a moment. 

“Saying that with that many layers is crazy.” He comments wryly. 

Gen pouts. 

“I’m a fragile being, Senku-chan. You are no different with your scrawny build and stamina.” 

“What’s that have to do with anything?!” Senku exclaims in a bristle. 

Gen grins mischievously.

“Many things, you know.” 

Senku flips him off before finally taking a sip from his tea. Chamomile tea, he notes. Someone clearly wants him to get proper shut-eye for once, or at the very least find comfort in something to ease his nerves for the upcoming war.

His dark eyes shift back to the telescope and the beautiful night sky behind it. 

Gen twirls the longer side of his hair as he watches the younger male carefully. He doesn’t blame him for his infatuation with stargazing. It truly is beautiful. Gen always went on long walks at night in the modern world to get a better view of the stars. Now he didn’t even have to try. 

Senku looks so peaceful compared to the usual tightness he wore in his expression during the day when instructing Ishigami Village around to prepare for warfare. 

It was nice. 

He looks way younger like this. 

A reminder that he is human, just like the rest of them. 

“I’m fine, you know. I’m not going to burst into tears and start venting my life's sorrows to you for your sake.” Senku deadpans, breaking the silence. 

A grin stretches its way across Gen’s lips before he sighs dramatically and flicks his wrist. 

“Well, it was worth a shot~”

“We both know damn well that wasn’t even an attempt. It would’ve been more layered with all that bullshit you and your mentalism contains.” The younger boy prods in an evident scowl. 

He’s getting impatient. Poking at Senku and getting animated reactions was always the best. 

In response, Gen merely shrugs him and his assumptions off. 

“Can’t I be lazy for once in my life? It feels like it’s a privilege these days…” He pouts.

Senku gives him a nasty side-eye in response. 

“You already slack off enough, mentalist. Now quit beating around the bush and spit out whatever you’re trying to cook up.” 

The older male sighs dramatically and brings a knee close to his chest so he can squish the side of his face against it. His bangs fall over unreadable, glistening eyes. 

“C’mon, Senku-chan! Relax for once! Or do I have to work my glorious magic on you to get your overworking brain to shut up?” 

His brows knit. He then lets out a sour “tch”. 

“Keep your ‘magic’ shit away from me.”

“Ah, but it isn’t magic! I’m a mentalist, after all~!”

“Y-You just called it magic!”

“Hmmm… maybe I did, maybe I didn’t~” He drawls. 

Senku’s expression is mashed tightly in a way that makes Gen’s lips quiver as he tries to not laugh. 

He tries to. Emphasis on that. Because the next thing he knows he bursts out laughing at such uncharacteristic agitation on the younger male’s face.

“Oh fuck off!” Senku grumbles and crosses his arms over his chest.

“Are you sulking?!” Gen sputters between giggles.

“No.” Comes a short, stiff reply. His ears that slowly tint red say so otherwise.

“You totally are!” 

Gen chokes on his own laughter as he cackles and doubles over. It’s free. Genuine.

Despite his embarrassment, Senku can’t help but smile a bit at that. 

It takes a few light swats and muttered ‘fuck you’s to get the two-toned hair male to finally calm down. His gray eyes are crinkled and shimmering with the dissipating tears of laughter. Gen wipes at his eyes with his sleeves and shuffles closer to Senku; obviously not close enough to invade the scientist’s personal bubble. 

Tea long forgotten, the pair gaze up at the starry sky, the telescope the only thing putting space between them aside from the mentalist’s mindfulness. 

Said male lets out a shaky sigh after prolonged silence, the result of previous boisterous laughter.

“They’re comforting, aren’t they?” He then speaks up softly, “the stars, I mean.”

Senku lets out a hum in response with his gaze glued to the sight. 

“I guess so. It’s just pretty exhilarating to know that such things have all been derived by science.” 

A pause.

“It sucks how we couldn’t get this sort of view in the modern world. You quite literally had to scavenge just to see a few stars. And even if you found a good spot without requiring going out into the wild, you still had to pay for it.” Gen rambles with a scowl, lips twisting into a comical pout.

Senku’s eyes flick at him momentarily, then his eyebrow raises. 

“You’re talking like you weren’t a damned celebrity back then, mentalist. Money was literally the worst of your worries,” the boy retorts whilst propping his chin on his hand, “unless it’s ‘cuz you just didn’t want to attract any attention.” 

“Bingo~!” Gen chirps, “that, and the fact that it feels more rewarding when you’re the one that finds the perfect place for it.”

Senku tilts his head in thought before letting out a small noise.

“I do get what you mean. It felt awesome, after hours of dragging my old man around, when you got the best view you could get.”

There’s a soft, bitter look in those eyes that draws out a bit of emotion from Gen. 

It was quite depressing to think about the life they used to have, torn from their hands just like that. The sole idea of trying to bring back humanity and the world to how it was is insane. Really insane. The pressure itself is suffocating, for the amount of life-or-death situations this sort of task has provided have already been too much to keep track of.

And they were only in the beginning. 

Gen sometimes wonders how Senku has kept his sanity intact until now. He knows he’s just as scared as he is, because who wouldn’t be, but just can’t help the thought. 

Maybe none of them were really sane to begin with. 

“Say, Senku-chan,” he starts slowly. 

“If you’re going to give me some dumb psychological lecture about me or something, please shut up from now.” Said male pipes up immediately. 

That draws out an involuntary snort from Gen.

“No, no. I just wanted to share facts and knowledge, eally-ray. But alas, if you don’t want to hear it, guess I should keep them to myself…” He exhales dramatically. 

He swears Senku’s ears twitched in response. Twitched.

God this dork of a human being is going to kill him one of these days.

“What’re you waiting for? Go on.” The teen before him urges, and wow he’s trying so hard to act nonchalant it is beyond amusing. 

Gen grins.

“I didn’t take you for a brat, Senku-chan~”

“Just shut up and tell me already.”

“But don’t you consider psychology a ‘waste of time’? A soft science?” 

The glare he gets in return is oh so impatient and annoyed that Gen has to bite his lip to stifle another fit of laughter. 

“Alright, alright. Tell me, Senku-chan. Do you have any background on pattern-seeking instinct?” 

“You mean the shit psychologists thrive off on? Pareidolia?”

“Yup~! Our brains are wired to find patterns no matter how random they are, so that’s why the people of the past connected stars into shapes like lions or hunters and whatnot.” 

Senku scoffs.

“That’s common sense, mentalist.” 

“Ah, but that’s where it gets deeper, Senku-chan~” Gen states with a lilt and a wiggling finger, “people thousands of years ago, obviously before the modern world, relied on the sky for farming, traveling and survival. These recognition patterns in the stars help predict seasons, navigation and harvest times. So, much to your preferences, it was basically early science shaken up to mix with their storytelling. Constellations were pretty much their hope and faith since they provided a full map and gave them stories, giving their lives rhythm and sense of stability. Pattern recognition is technically both rational and emotional, after all.”

Senku’s brows dip.

“Emotional?” He echoes. 

Gen cocks his head and shifts himself so he faces Senku fully.

“Yes, Senku-chan. Emotional. Something you’re quite revolted by.”

The glare he gets makes him snicker.

“Now, now, don’t get all sour on me now. I’ll explain. The stars and constellations are a form of emotional comfort for us human beings. It’s eriously-say interesting, how much one can resonate with the stars above. The people from way before quite literally projected their identities on the stars from how much they helped them. They saw their myths, values, and fears reflected in those beautiful specks in the sky. All these names we now know of are from them. Heroes, animals, or gods, they were really just expressing themselves and their culture.”

Senku’s eyes trailed onto him, glimmering with such genuine interest and desire to learn, makes Gen’s heart stagger. 

“Wouldn’t… what’s it called… awe… have some sort of influence as well?” He inquires with pure curiosity. 

Gen seriously might cry. Such an innocent expression on the other’s face makes him look even younger and squishy. Yeah, he wants to squish the life out of him because damn he looks so young Gen might even call it adorable. 

“You get points for that, Senku-chan! As it’s defined, awe is a complex emotion that blends wonder, smallness, and admiration all into one. So when someone looks up at the starry sky, their brain realizes they’re a part of something unknown.” 

“An enormous mystery.” Senku mumbles.

“Exactly~! When one processes such a thing, it activates parts of the brain tied to curiosity and emotional regulation and quiets the areas linked to self-focus. That’s why your thoughts go quiet when you stargaze, because your sense of ‘self’ expands. At the same time, awe helps you think more openly and connect ideas that normally wouldn’t. That’s how people before modernity imagined stories, myths or big questions. That’s why you think, ‘what’s out there?’ or ‘what am I part of?’ It’s the same feeling that inspired ancient myths and modern science— both creative ways of explaining the stars. That’s also why you tend to feel like you’re able to produce more results, Senku-chan. Because awe has proven to make us more imaginative”

Instead of taking it personally, said scientist looks amazed.

“Damn…” He musters.

“Right?”

Senku grins broadly as he meets Gen’s crinkled eyes. 

“I really should’ve considered reading more than I did on psychology back then, huh? Pretty fucking exhilirating.” 

The teen then scratches the side of his face thoughtfully then lets out an amused chuckle.

“I didn’t take you as someone to have a shit-ton of knowledge of their own. You keep surprising me, mentalist.” Senku smirks.

Gen offers a perplexed look in response.

“I eally-ray don’t know if that’s a compliment or an insult, Senku-chan…”

Instead of trying to clarify, the ecstatic glint in his eyes increases.

Gen can already feel a rant beginning to rise.

It’s not like he’s complaining. 

“The question is, now that you’ve brought up interesting facts, are constellations more a reflection of the universe or of the human mind? Because when you think about it, many things psychologists and scientists have deduced link in some sort of way but also clash. For instance, if we consider subjective experience and objective reality, we can understand that…”

Senku’s head constantly moves back and forth between the vast expanse of stars and Gen, hands moving in erratic gestures as he spouts the questions and theories in his mind. His cheeks are flushed a light pink in excitement, expression unguarded and softer; happy. Youthful excitement emits from him in a way that makes Gen feel mushy.

Gen is listening and contributing to the debate-like conversation, but he can’t help admiring such sincereness to the boy. He truly sparkles when he lets loose and indulges in what he adores most. 

He notes that those red eyes really do compliment the sky. They almost look like they have stars engraved within the pupils. 

That’s right. 

There were stars engraved in the young scientist’s eyes. The universe is what that crimson gaze held. 

How awfully poetic. Gen thinks to himself with a small noise of amusement. 

“What’s so funny?” Senku inquires as he cuts his ecstatic ramble short with a raised eyebrow.

A small, genuine smile traces itself onto Gen’s lips.

“Nothing at all.” You’re just one of a kind. 

Senku squints at him momentarily, suspicion etched on his face, then shrugs it off and continues his endless facts with waving hands. 

They spend the rest of the night sharing facts and bickering until sleep consumes them.

And the stars have never shone so brightly.