Chapter Text
“Ack!” you hissed, snapping your wrist after another sharp jolt. You’d stopped counting how many times the static had zapped you. Dust clung to your skin until you felt like the nucleus of a plasma globe.
Senku had dumped you in the village laboratory with yet another mind-numbingly tedious task—grinding down sulfur, charcoal, and a handful of other gray minerals into fine powder.
The generator humming threateningly nearby didn’t help.
“‘Even a baby could do it’ ? Go to hell,” you muttered, rolling up your sleeves. You pressed the pestle back into the mortar, each grind more grudging than the last, the rasp of stone on stone matching the irritation buzzing in your veins.
Your hand swept across the cluttered tabletop of the lab, grasping at empty air where the mineral should have been. You turned, scanning the jars and trays again, but it was gone. A resigned sigh pushed through your teeth as you stood to check properly.
Still missing. Which meant another trip to the storehouse.
You headed for the door, only to catch one last static snap from the generator on your way out.
“Ugh—damn it!” you spat, shaking out your hand.
The chill of night hit you the moment you stepped outside.
You slipped into the storehouse, greeted only by the faint creak of the door.
“Seems like Chrome is sleeping in the village again,” you murmured, noticing his absence. Night duty was yours alone. Sometimes Kinro nodded by at the bridge before dawn if he happened to wake early, but after yesterday’s brutal training, even he was out cold.
Being a night owl in the old world had meant dragging yourself through mornings half-dead, teachers side-eyeing you for yawning through class. Here, it was a different story. No one minded if you stayed awake under the moon. No one except Senku, who only called you “lucky” for not getting grilled with questions like some all-knowing oracle of science.
You moved down the rows of glass containers, eyes flicking over their dull shapes. The mineral you needed had to be here somewhere.
…Wait. Which mineral was it again? They all looked exactly the same.
You groaned, dust clinging to your sleeves, fingers hovering uselessly over the jars. The static prickled your arms again, making you flinch.
Your eyes drifted to the wooden roof above, the little door where Senku usually slept. A part of you thought about trying to sort them yourself—but then his voice floated back, dry and smug:
“Seriously, even a baby could do this. Just sort by size or color. Basic observational skills, Graveyard Shift.”
You muttered under your breath, “Yeah, thanks, genius,” and shook your head. Picking up two sample minerals, you squinted, turned them, tapped them together, and still couldn’t see a difference.
Clearly, Senku had overestimated your ability to tell these rocks apart.
Sighing, you climbed up the step ladder to the observatory. Looks like it was time to wake Senku. Hopefully he’d be less annoyed than he would be tomorrow when faced with half the powder he expected.
You heaved the door over your head, muscles tense as the hinges groaned.
“Wake up, you damn…” Your words caught in your throat as your eyes fell on the scene inside.
The moonlight fell across him, highlighting the sheen of sweat on his skin. Loose cloth clung unevenly, shifting with every sharp breath he drew. His chest rose and fell rapidly, the rhythm erratic, the quiet panting filling the room.
White drops glimmered on the floor near him, and your gaze darted to his hand, in motion. Startled, you lost your grip on the trap door. It swung down sharply, smacking the back of your head with a painful thud.
Senku’s eyes widened the instant he noticed your gaze, embarrassment flaring across his features. A flush spread rapidly from his neck to his cheeks, sweat glistening even more under the moonlight. His lips parted as if to speak, then snapped shut, and his hand froze mid-motion.
And that was the day your gruelling tasks were increased threefold.
———
It had been a week since… that incident. And ever since, Senku had been cold to you, acting like it was somehow your fault.
Maybe it made sense, in a twisted way. You’d be mortified too if someone walked in on you flicking the bean—your most private, ridiculous moments exposed for some person to see.
But, c’mon. You had definitely paid the price.
You had been unfairly tasked with heavy-duty work all morning, hauling heavy sacks that left your arms trembling. Hours had passed, and by the time the sun climbed higher in the sky, it was nearly noon—your sacred, dozing time. Your body ached, and every nerve felt frayed.
Kohaku had noticed your sluggish gait and waved you over to the river. “Come on, take a break. You look like you’re about to collapse,” she said with a small smile.
Now, sitting on the smooth rocks at the water’s edge, you gazed into the river, watching sunlight scatter across the surface. The gentle lapping of water seemed to pull some of the tension from your shoulders. For a few moments, neither of you spoke.
Then Kohaku broke the silence, her voice soft but curious. “What’s eating you?”
You hesitated, cheeks warming. “…So, hypothetically,” you began, stumbling over your words, “what would you do if you… maybe, hypothetically, of course, saw someone kind of naked?”
You carefully left out the part that you saw Senku giving Lil’ Senku a workout.
Kohaku blinked at you, calm as ever. “It’s natural. Happens all the time.”
You groaned, whining. “No, it’s not!”
She leaned closer and playfully nudged your shoulder with hers. “We’re both naked right now.”
You froze. “…Yeah, but it’s different. We’re both girls.”
Kohaku’s expression was amused, matter-of-fact. “Even if we weren’t… wouldn’t it still be ordinary?”
Your gaze dropped to the water, your thoughts spinning. Of course—her era wasn’t as modest as yours. Accidents like this didn’t carry the same weight for her.
You flopped back against the smooth rock, tugging at your wet hair. Kohaku’s calm gaze never wavered. “Look,” she said, finally, “if it bothers you this much, there’s only so much you can do. You’ve got to… deal with it.”
“Deal with it?” you repeated, incredulous. “How? By pretending it didn’t happen?”
She shrugged lightly. “Exactly. Move on, live your life.”
You chewed your lip. “I think… I’m more worried that he’s more embarrassed than I am.” Your voice dropped, almost a whisper. “Like I walked in on something private, and now he hates me or is angry at me…”
Kohaku gave a soft sigh, shaking her head. “You’re overthinking it. Seriously. Most of the time, people are too busy to dwell on what you saw. But…” She leaned back slightly, her tone gentler, “if it would calm your mind, maybe a simple apology would help. Just… acknowledge it without making a big deal. That’s it.”
You stared at the water, splashing lightly at the surface. Apologize. Keep it small.
Kohaku leaned back, letting out a quiet sigh. “Honestly, it’s really not that big of a deal.”
Just then, a chirpy, overly enthusiastic voice carried from the distance. “Ya-Ho! Mind if I join in?”
Without missing a beat, Kohaku spun around, eyes blazing, and shook her fist in the air. “Gen. You perverted, sleazy man!” she shouted, her voice echoing across the river. “Not another step!”
Gen’s voice carried from the distance, muffled but dramatic. “Kohaku-chan… so cruel!” you heard him cry as he slinked away, still whining about being chased off.
You couldn’t help a small, amused smile despite yourself. Turning to Kohaku, you said softly, “Thanks… for the advice.”
She shrugged, brushing water from her hair. “Don’t overthink it. Just… be honest, keep it simple.”
“I will,” you promised, taking a deep breath. “I should go apologize.”
You slipped out of the river, the cool water leaving goosebumps across your skin. After quickly getting dressed, you made your way to the lab.
The room was quiet, the afternoon sun spilling across the countertops. Senku was there alone, tinkering with some apparatus, his usual focused expression in place.
You stepped inside cautiously. He glanced up from his work. “What do you want?”
You shuffled your feet, suddenly aware of how stiff your arms and shoulders felt. Words caught in your throat, and instead of blurting out that you were there to apologize, you asked nervously, “Uh… what are you doing?”
Senku didn’t look up immediately, carefully adjusting a tiny component. “I’m building a headlamp,” he replied, his tone casual but precise.
“Oh… a headlamp?” you repeated, voice a little higher than usual. “What’s it for?”
His eyes flicked to you, sharp and calculating. “Headlamp. Lamp for the head. If you had all that time for stupid questions, you’d have plenty of time to finish another chore,” he said, already returning to his tinkering.
You groaned, realizing your attempt to ease the tension had backfired. “I—uh—I’m sorry.”
For the first time, Senku set his gadget down and finally gave you his attention. “You still haven’t learned to knock on the door.”
You froze, then turned around. “…Right. I didn’t knock.”
“That’s what I said,” he said flatly.
“It was… last time it was a trap door, not an actual door,” you mumbled.
Senku scoffed. “There’s door in the name. That should’ve been enough.”
You felt heat rush to your cheeks. “…I know, I know…” you muttered under your breath, glancing down at the floor. Your fingers twisted nervously. After a long pause, you tried again. “…It’s… it’s normal. You were… jerking off. It’s not… that embarrassing.”
His eyes narrowed, sharp and calculating, making your stomach twist. “This is about your lack of manners. Why are you blaming me?”
You shook your head quickly, stumbling over your words. “I’m not blaming you! I get it… I mean… sometimes even I get horny too, you know?”
Senku looked up, one eyebrow raised. “Don’t compare your… primitive urges to my quick stress relief method. Totally different systems at work.”
You blinked, tilting your head. “…Aren’t they practically the same thing, though?”
He sighed, as if he couldn’t believe you needed this explained. “No. I’m doing it for efficiency. You’re doing it for pleasure. That’s the fundamental difference.”
You chewed your lip, cheeks warming, trying to figure out how to say it. “…But doesn’t it come down to the same thing, in the end? Both of us just… trying to feel better?”
Senku gave you a flat look. “No. I’m cutting down tension so I can keep my brain running at full capacity. You’re chasing dopamine for the fun of it. Two entirely different categories.”
Your mouth twisted. “Okay, fine, Mr. Science. Stress relief, mental clarity, whatever you want to call it. But it’s still your body. It’s not like you can separate it from… y’know.”
He exhaled through his nose, sharp and impatient. “You’re circling back to pointless semantics.”
Well… you’d already dug yourself a hole. There was no turning back now. Every blush, every fumbled word from earlier made the idea of saying anything even more terrifying—but staying silent wasn’t helping either.
“Maybe,” you muttered, eyes dropping to the floor. “But… I keep thinking there has to be a way for both of us to get what we want without… all this awkwardness.”
That made him pause, crimson eyes narrowing slightly. “…Both of us?”
You nodded, throat tight. “Yeah. You don’t want anyone barging in again, and I…” You hesitated, heat crawling up your neck. “I wouldn’t mind if… I got something out of it too.”
His stare sharpened, voice low. “What exactly are you proposing?”
Your pulse spiked, but you forced the words out. “Well… you could… provide me, uh, dopamine whatever while I… help with your stress relief in return.” A beat passed before you blurted, “So… sex.”
Senku’s eyes narrowed, unamused. “Why would I want to agree with that?”
“You… you wouldn’t have to worry about anyone walking in anymore,” you added quickly. “Since I’m usually the only one awake at that hour.”
He raised an eyebrow. “That’s not enough of a reason to involve us together.”
You felt heat rise to your cheeks. “It takes too long for me on my own. Doing it together… could save both of us time.”
Senku leaned back slightly, expression deadpan. “So you’re proposing time management… through a sexual intercourse. Brilliant. Absolutely not.”
You blinked, cheeks burning. “…I’m serious! Think about it. You get your stress out, I get un-horny. It makes sense.”
Senku stared at you for a long moment, expression unreadable, before letting out a sharp sigh. “No. Absolutely not. Your nocturnal ass is drowsy at 3pm. That brain reacts similarly to being drunk. You are literally impaired, and your judgment is completely unreliable right now. I am not listening to another word of this.”
You groaned, pressing your palms to your face, cheeks aflame. “…I'm still conscious,” you muttered, voice muffled.
Senku’s eyes narrowed, and he waved a hand dismissively. “Go on. Get out of here before I assign you another chore. And trust me, I will if you linger with more of these… hypothetical experiments.”
You let out a long, frustrated sigh and stepped back, retreating from the lab.