Chapter Text
The morning air in New Shanghai was thick with the scent of damp earth, cooling embers, and the bittersweet realisation that the party was also a farewell. The village, now humming with the steady pulse of a rudimentary electrical grid, was no longer a collection of survivors — it was a colony. But as the Perseus prepped its boilers, the reality of a world split by distance began to set in.
Wang and Da Wei stood near the newly built storage shed, already organising the first shipment of raw latex. For them, there was no question; this was home. They had spent a year in the dirt of Shanghai, and they would see its rebirth.
However, near the gangplank of the ship, a much more painful negotiation was taking place.
"You can't stay here, Professor," Han Gengo said, her voice trembling as she clutched her linguistics notebook. Her eyes were red-rimmed, a mix of the previous night’s exhaustion and the impending grief of departure. "The Perseus has the medical facilities. The Kingdom of Science needs your knowledge of the archives. I... I need you to come with us."
Professor Chen stood hunched over his walking stick, his eyes fixed in the direction of the ivy-covered ruins of Nanjing Museum. He looked older in the morning light, a man whose life had been a series of excavations and long-buried truths.
"Han-chan," he said softly, using the familiar Japanese suffix he had adopted from her. "I have spent twenty years of my first life and two decades of my second chasing the ghosts of this city. To leave now, when my life’s work has finally breathed again... it would be like leaving a book halfway through the final chapter. My place is here, in the dirt of my ancestors."
"But I’m going back," Han argued, a single tear escaping. "Senku-san needs a bridge between the Tokyo settlement and the New Shanghai colony. I’ve decided to stay with the Kingdom of Science... as the official Chinese Ambassador. If you stay here, I won't have my teacher."
Chen offered a frail, heartbreaking smile. "You are no longer a student, Han. You are an ambassador. You speak the languages of two worlds. You don't need a sickly old archaeologist to hold your hand. You have your whole life ahead of you — one you have already spent so long living in without me."
The heavy, emotional weight of their parting was suddenly interrupted by a sound from the ship’s upper deck — the metal-on-metal creak of the cabin door opening.
A hush fell over the gathered group.
Maomao stepped out into the light. To the Moderns and the Li Dynasty survivors alike, the visual cues were unmistakable. She was wearing the exact same green wrap from the night before, now hopelessly rumpled. Her hair, usually kept in a disciplined bun with her titanium pin, was a wild, dark thicket. Most tellingly, the silk ribbon she usually used the previous night was gone; in its place, her hair was tied back with a jagged, roughly torn strip of white fabric — an unmistakable piece of Senku’s lab coat.
Senku followed a second later, looking equally dishevelled, a matching missing patch on the hem of his coat fluttering in the breeze.
"Oh," Gen purred from the bottom of the gangplank, his fan snapping open with a sound like a gunshot. "A walk of shame? And here I thought the Kingdom of Science was focused on building furnaces last night."
Jinshi, standing near the crates, went remarkably pale. His hand tightened on the hilt of his sword until the leather grip creaked.
"Maomao," Jinshi managed, his voice strained. "You... you stayed in his quarters."
"It was a logical necessity," Senku shouted down, picking a piece of lint off his shoulder. He could imagine what the former emperor was asking. "The lead pharmacist was in a state of ethanol-induced equilibrium loss. Movement was ten billion percent inefficient."
"I couldn't walk last night," Maomao added, her voice flat, though a faint, lingering flush touched her ears. "And I lost my ribbon in the confusion. Senku was merely... providing a solution."
Pairin and Meimei were already giggling behind their hands, their eyes darting between the dishevelled Maomao and the uncharacteristically awkward Senku. "A solution," Pairin mimicked. "Is that what they call it in the future?"
Maomao looked at the smirking crowd, then at the devastated Jinshi, and finally at the judgemental eyes of the New Shanghai residents. The embarrassment that had plagued her earlier that morning suddenly calcified into a sharp, defiant irritation. She was tired of being the merchandise; she was tired of being the statue.
She took a deliberate step forward, her chin lifting as she met Gen’s gaze with a challenging, unblinking stare.
"Yes," Maomao said, her voice carrying clearly across the deck. "We slept in the same bed. I was incapable of letting go of his sleeve, and he was incapable of removing me. Does anyone here have a biological or professional problem with that?"
The silence that followed was absolute.
"Because if you do," Maomao continued, her eyes sweeping over the Li warriors and the modern labourers, "I suggest you take it up with the Chief of Science. Otherwise, we have a furnace to build and a ship to sail. We are wasting daylight on gossip when we should be sailing."
She turned and marched towards the galley, the strip of Senku’s lab coat fluttering like a white flag of war in her hair.
Senku watched her go, a slow, manic grin spreading across his face. He looked down at the gap in his coat, then back to the stunned crowd.
"You heard the lady," Senku remarked, leaning against the railing. "Ten billion percent more work to do. Professor Chen, Han-chan — finish your farewells. Ryusui is doing the crew manifesto in an hour. We have a world to rebuild."
~~~
The deck of the Perseus was a crowded stage of clashing eras as Ryusui Nanami stood before the Li Dynasty survivors, his fingers snapping with the rhythm of a man counting his most valuable assets. Beside him, Professor Chen clutched his notebook, his eyes darting from the "Last Emperor" to the legendary beauties of the Verdigris House with a fervour that bordered on religious ecstasy.
"Greed is justice!" Ryusui announced, his voice booming over the sound of the steam vents. "But greed requires a cold, hard look at the ledger. We are sailing for the Tokyo settlement, but the Perseus is no merchant cog. We are a vessel of exploration and, eventually, war. The journey beyond Japan will be ten billion percent more dangerous than a river cruise."
Chen translated frantically, his voice cracking when he reached the word for war. The atmosphere shifted instantly.
Pairin gripped the railing, her exuberant confidence flickering. "Danger is one thing when it’s a rival concubine with a vial of lead powder," she muttered in the Li dialect. "It's another when the world itself is trying to turn you back into a rock."
Ah-Duo stepped forward, her hand resting on Pairin’s unsure shoulder. The former consort looked remarkably composed, her skin glowing with a vitality that seemed to defy the centuries. She looked at Ryusui, then at Maomao, who was standing near the galley.
"We will go to Japan," Ah-Duo said, her voice carrying a weight of quiet authority that even Chen struggled to translate without bowing. "But once we reach your settlement, I believe the Rear Palace has seen enough of the front lines. The petrification light... it is a terrifying thing, but it is also a miracle."
She paused, a small, private smile touching her lips as she looked at Jinshi. "My body has been reset. The scars of the past, the internal damage that stole my future... it is all gone. I am a woman who can have children again. I do not intend to squander that second chance in the belly of a warship."
Pairin nodded vigorously. "She’s right. And I have a big, strong lug of a guard to look after," she added, shooting a wink at Lihaku, who looked like he wanted to merge with the ship’s hull. "Japan sounds like a fine place to build something that isn't made of stone."
Meimei, however, didn't share their caution. She looked at the horizon with a restless, bright-eyed hunger. "You can stay behind and knit socks, Pairin. I want to see what else the 'future' has tucked away. If the Kingdom of Science is going to go around waking up the world, I want to be there when the curtain goes up."
While the women debated their futures, Lihaku stood as a silent, troubled pillar between the two groups. His eyes flickered to Jinshi, his master, the man whose birthright he had been sworn to defend with his life. Then, his gaze shifted to Pairin — the woman who represented a life he had never dared to dream of, a life of simple choices and earned happiness.
Lihaku saw the way Maomao stood now — hair tied with a piece of Senku’s coat, unbowed, unbothered by the shame that would usually be a death sentence where they were from. She had chosen. She had discarded the mandate of heaven for the truth of the earth.
Lihaku swallowed hard. He felt the phantom weight of the Imperial crest on his shoulder, a burden that felt heavier than the timber he hauled. He wanted to say that he wanted to stay with Pairin. He wanted to say that the idea of an emperor felt like a dusty relic in the face of a man who could command lightning. But the words of a common soldier were not so easily untethered.
"I will stay in Japan," Lihaku blurted out, his voice a bit too loud. He didn't look at Jinshi. "The settlement... it will need protection while the Perseus is away. Someone has to ensure the sisters and the Lady Ah-Duo are safe from the 'natives' and the predators. I am a guard. That is my capability."
It was a clumsy excuse, a compromise between the duty he couldn't quite abandon and the freedom he was starting to crave.
Jinshi looked at him, his expression unreadable. He saw the way Lihaku avoided his gaze, and he realised with a sharp, cold pang that the first defection from his empire wasn't Maomao — it was the very men who were supposed to be his foundation.
"A guardian for the home front!" Ryusui snapped his fingers, delighted. "An excellent allocation of resources! Lihaku, you shall be the Shield of New Tokyo! Pairin, Ah-Duo — you shall be our cultural advisors!"
Professor Chen was scribbling so fast his lead snapped. "A monumental shift!" he whispered to no one in particular. "The dissolution of the Imperial Guard in favour of domestic security! The birth of the first truly modern Chinese expatriate community!"
As the crew began to haul up the anchor, the division was set. The Perseus would carry them all to Japan, but once they arrived, the statues of Li would truly shatter, not into dust, but into individual lives, each choosing their own path in a world that no longer cared about the colour of their robes.
~~~
The radio hissed, a jagged sound of atmospheric interference crackling through the receiver on the bridge. Senku leant over the console, his brow furrowed as Ruri’s voice broke through the static, sounding thinner and more strained than he had ever heard it.
"Senku... can you hear me?"
"Loud and clear, Ruri. What’s going on?" Senku’s eyes were concerned. Senku considered Ruri a good acquaintance despite her not coming along on the voyages. It was her recovery that helped spark the Kingdom of Science’s success thus far.
Some would argue the term "good acquaintance" was reductive, considering she was his ex-wife.
"We have a situation in Tokyo. It’s... there is a sickness. We suspect a toxin." Senku stayed silent. "We are using the tinctures and notes Maomao left, but it’s not enough. People are fading. We need... help."
"Yeah, got it. We’re on our way back. Stay safe for now. I’ll ask Ryusui to put this boat on hyperdrive. Senku out."
"Thank you, Senku. Ruri out."
Senku’s hand tightened on the dial, the static hum filling the room as the connection cut. A poisoning? In a world where he personally accounted for every refined chemical and industrial byproduct? That was ten billion percent improbable — unless there was a variable in the Stone World ecology he had fundamentally missed.
"Poi-son?" a voice asked from the doorway.
Loulan stood there, clutching her linguistics notebook. She had been studying with a hunger that rivalled Senku's own, her eyes sharp and observant. She stepped into the bridge, her Japanese broken but the intent behind her words striking with the force of a hammer.
"Hey, uh… sorry, I forgot your name already. You’re Maomao’s friend, aren’t you?"
"Maomao," Loulan began, her brow knitted as she searched for the vocabulary. "Before stone... she... Search. Finder. Jinshi call. She find... truth. Find poison. Find killers."
Senku’s eyes widened. He had known she was a master of chemistry, a pharmacist who navigated the biological minefield of an Imperial Court, but a detective?
"You're telling me she wasn't just mixing the potions; she was hunting the people who used them?" Senku muttered, a sharp, manic grin slowly spreading across his face. "Ten billion percent... I really found a legendary drop, didn't I? Wonder why she didn’t tell me."
"Ryusui!" Senku shouted into the microphone nearby, "Change of plans! Forget the slow-burn return! Fire up the secondary boilers and push the turbines until the rivets scream! We’re heading back to Tokyo at top speed. The Kingdom of Science has an incident to solve, and I want our apothecary on the case before the toxin finishes what the stone started!"
Ryusui’s laughter echoed through the room, punctuated by the sharp snap of his fingers. "A race against time? A high-stakes gamble for the lives of our citizens? That is the greediest request I’ve heard all month! Full speed ahead!"
~~~
The damp morning air of New Shanghai clung to the Perseus as the final crates of raw latex were secured into the hold, marking the official end of the China expedition’s founding phase. Below the gangplank, the heavy, emotional gravity of the departure centred on two figures: the sickly, hunched Professor Chen and his once-student, Han Gengo. Han, now the official Chinese Ambassador to the Kingdom of Science, stood at the base of the metal ramp, her linguistics notebook clutched to her chest as if it were the only anchor left in a shifting world.
Professor Chen offered a frail, heartbreaking smile, his eyes fixed on the student who had surpassed his own mastery of the modern tongue. Without a word, Han surged forward, wrapping her arms around the old archaeologist in a long, silent hug that bridged forty centuries of shared history. Chen patted her shoulder with a weathered hand, a gesture of quiet blessing before he stepped back into the dirt of his ancestors, choosing the ruins of the Nanjing Museum over the high-speed progress of the 21st century.
The heavy iron doors of the Perseus’s laboratory hummed with the vibration of the ship’s engines. Outside, Ukyo Saionji leant against the bulkhead, his arms crossed and his keen ears picking up the rhythmic thump-thump of Maomao’s mortar and pestle inside. When Senku emerged, wiping a smudge of unknown chemical residue onto his lab coat, Ukyo didn’t waste time.
"Why haven’t you told her already?" Ukyo asked, his voice low but pointed. Senku wasn’t surprised he’d heard the news already. "We have an entire faction of survivors who were nearly wiped out by a toxin we don't fully understand. If there’s a risk of secondary exposure or a lingering environmental threat, shouldn't our primary expert be briefed on the strategic details?"
Senku adjusted his collar, his eyes trailing towards the stairs leading up to the deck. "She’s occupied. And honestly, Ukyo, her focus is better spent on the vials than the politics right now. Besides, I have something else I need to ask her."
Ukyo’s brow furrowed. He stepped into Senku’s path, his expression one of rare, genuine confusion. "Something else? Senku, we’re talking about a potential biohazard situation. What could possibly be more important than briefing your lead pharmacist on a poisoning case?"
Senku stopped. He didn’t offer his usual manic grin or a dismissive lecture on the laws of physics. Instead, he looked up at the ceiling, his expression uncharacteristically guarded.
"Something very important," Senku said quietly. "Something that isn't about chemicals or empire-building. It’s… logistics of a different nature."
The silence that followed was heavy. Ukyo searched Senku’s face, his sensitive hearing picking up the slight, irregular hitch in the scientist’s breathing—a physiological tell that had nothing to do with exhaustion or illness. The realisation hit Ukyo with the force of a physical blow. He wasn't talking about a new invention or a medical breakthrough. He was talking about her.
Ukyo’s posture softened, his shoulders dropping as he exhaled a long, slow breath. He was a man of peace, a man who could hear a heartbeat from a mile away, but the intricate, messy landscape of the human heart was a territory he had never successfully charted for himself.
"I see," Ukyo said, stepping aside to clear the way. He held up a hand as if to ward off any further explanation. "If it’s that… then I’ll leave you to it. I have no desire to interfere in matters where I have neither the jurisdiction nor, frankly, the expertise."
"Ten billion percent for the best," Senku muttered, already moving towards the deck. "It’s a variable I’m still trying to solve for anyway."
Ukyo watched him go, a small, wry smile tugging at the corner of his mouth. Even the man who could rebuild civilisation from scratch, it seemed, was not immune to the one force that didn't follow a formula.
As Ryusui snapped his fingers to signal the release of the moorings, the Perseus began to groan, its secondary boilers pushing the turbines until the rivets began to vibrate. The residents of New Shanghai — Wang, Da Wei, and the others who had chosen the rebirth of their city — lined the riverbank, waving until the ship was a mere speck against the green-choked landscape.
The survivors of the Li Dynasty stood at the stern, a wall of living history watching their empire truly vanish for the second time. Jinshi watched the trees covering his former home sink beneath the tree line, his hand white-knuckled on the railing.
~~~
The sun was high over the Perseus, turning the salt-crusted deck into a bleached stage where two eras collided with every step. Suika, ever the diligent scout, had taken it upon herself to bridge the gap between the Kingdom of Science and their new, ancient passengers. With her melon rind tucked under her arm for the moment, revealing a face of earnest curiosity, she scurried through the throng of Li Empire survivors.
"Hello! I’m Suika!" she chirped, bowing low to a group of men hauling crates. "If you need to know where the fresh water is kept, I can show you!"
The men paused, wiping sweat from their brows, and exchanged bewildered glances. One of them offered a polite, hesitant bow back, but his reply was a string of melodic, archaic Mandarin that left Suika tilting her head like a confused bird.
"I… don’t think that was a ‘yes,’" Suika muttered, undeterred.
She pivoted toward the upper deck, where the three princesses of the Verdigris House were lounging. Pairin and Meimei spotted her instantly. To them, the sight of a small, round-faced girl in a primitive tunic was a novelty too precious to ignore.
"Oh, look at her!" Pairin squealed, her voice a silk-wrapped bell. She moved with a fluid grace that made the ship’s swaying seem intentional, kneeling before Suika and immediately reaching out to pinch her cheeks. "Like a little peach! Is she a forest spirit, Meimei?"
"She’s far too cute to be a spirit," Meimei laughed, joining her. She began fussing with Suika’s hair, her fingers expertly smoothing out the tangles caused by the sea breeze.
Suika felt like a doll being handled by giants. "I’m a member of the Science Team! I help with reconnaissance!" she insisted, though it was muffled by Meimei’s silk sleeves.
"She’s making such fierce little noises," Pairin cooed, completely missing the Japanese entirely. "Do you think she belongs to the Alchemist?"
"She belongs to herself," a calm, masculine voice interrupted.
Jinshi approached, his presence causing the two courtesans to straighten instantly, their playful demeanour shifting into a practised, elegant deference. He looked at Suika, his eyes reflecting the months of gruelling study he had endured under Maomao’s silent, judgemental gaze.
"Suika," he said, the name feeling heavy and deliberate on his tongue. He struggled for a moment, piecing together the grammar of the 'Stone World.' "You… are doing… well?"
Suika’s eyes lit up. "You speak Japanese! Mostly!"
Jinshi gave a small, weary smile. "A little. I must. For… communication." In truth, he had spent his nights memorising kanji by the light of a flickering lamp specifically so he wouldn't be left behind in the conversations between the apothecary and the scientist.
Nearby, leaning against the railing, Loulan watched the scene with her usual detached, cat-like observation. She didn't look at Jinshi or the sisters; her eyes remained fixed on Suika as the girl began explaining the mechanics of a pulley system to a nodding, yet clearly lost, Jinshi.
"She reminds me of Xiaolan," Loulan remarked, her voice barely a whisper against the wind.
Maomao, who had been grinding dried herbs against a small stone mortar, paused. Her hands, stained with the green residue of a dozen different plants, went still. She looked at Suika—the girl who had survived the wilderness, who had risked her life to deliver sulfuric acid, and who had become the eyes and ears of a technological revolution.
"I used to think so, too," Maomao replied, her voice flat but not unkind.
She remembered the laundry girl in the Rear Palace—simple, bubbly, and blissfully unaware of the poisons that moved through the air. Xiaolan was a creature of the sun who thrived in the safety of the walls.
"But not anymore," Maomao continued, resuming her grinding. "Xiaolan was a girl who lived in a world that was already built. Suika is helping to build one from the dirt. There is a hardness in her that Xiaolan never had to find. It’s a pity, in a way. But it’s also why she’s still breathing."
Loulan didn't respond, her gaze lingering on the girl. On the Perseus, innocence wasn't lost. It was simply forged into something more durable.
~~~
The following night, the Perseus cut through the dark expanse of the East China Sea with a steady, rhythmic groan. The stars above were needle-pricks of light, indifferent to the shifting eras below. For Maomao, however, the primary concern was not the celestial bodies, but the vertical challenge of the mast.
Her calf muscles burned with a dull, insistent ache as she hauled herself upward. The salt air made the ropes slick, and every pitch of the ship felt like a personal insult to her equilibrium. By the time her head cleared the floor of the crow’s nest, her breath was coming in short, sharp hitches.
Senku didn't look up from the brass-bound telescope he was recalibrating. The moonlight caught the sharp lines of his profile, turning his lab coat into a ghostly shroud against the darkness.
"You’re three minutes slower than Kohaku," he remarked, his voice carrying easily over the rush of the wind. "Though, to be fair, she doesn't usually stop to glare at the rigging halfway up."
Maomao hauled herself into the cramped, swaying space, smoothing her damp wrap with trembling fingers. She pointedly ignored the remark about her climbing speed.
"I have yet to find a valid reason to develop the leg muscles of a mountain gorilla," she replied, her voice steadying as she sat back against the wood. She looked out at the dizzying drop to the deck, where the lanterns looked like dying embers. "Why does anyone come up here? The air is thinner, the wood is damp, and if the ship pitches too hard, you become a very high-velocity projectile. More importantly, why was I asked to come up here? I am a pharmacist, not a sailor."
Senku finally pulled back from the eyepiece, his fingers clicking a dial into place. He turned to look at her, his expression unusually subdued. There was no manic light of discovery in his eyes, only a grounded, heavy sincerity that Maomao found far more unnerving.
"Logic dictates that the higher the vantage point, the less atmospheric interference," he said, leaning back against the railing. "But you're right. I didn't bring you up here to look at the stars or to teach you how to tie a bowline knot."
He let out a short, dry exhale, looking out at the horizon where the sea met the blacker sky.
"Out of the seven billion people on this planet — whether they’re still statues or walking around right now — there’s no one else I’d rather have this conversation with. Most people look at the world and see what they can take from it. You look at it and see how it works, even when it’s trying to kill you. That’s a rare demographic."
Maomao watched him, her hand instinctively moving to the titanium pin in her hair. The wind whipped a stray lock of hair across her face, but she didn't look away.
"You're being uncharacteristically sentimental," she noted, her voice low. "It usually precedes a very expensive request for chemicals."
Senku smirked, but it didn't reach his eyes. He tapped his fingers against the wooden rim of the nest.
"Not this time. No chemicals required. Just a shift in the organisational chart." He turned his head slightly, catching her gaze. "Tell me, Maomao. How would you like a promotion?"