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Written in Stone

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Senku decided pretty early on that he didn’t care too much about the whole soulmate thing. There was no science behind it, no logic, no reason! No matter how many questions he asked and how much research he did, the answer was still the same, nonsensical junk every time.

It’s just fate! The universe decides! It’s written in the stars!

What did fate have to do with anything? How could the stars and planets be deciding things like who Senku was supposed to love? The whole thing made no sense and everyone was just full of it in Senku’s opinion.

So no, Senku didn’t care too much about the idea of soulmates and the words printed onto his skin didn’t bother him too much.

But he was only human. So he couldn’t be blamed if once in a while, when he passed in front of a mirror, he stopped and took a second to carefully inspect the neatly written words that ran just below his collar bone on the right side of his chest.

“This seriously makes me wish I had something to drink…. Like a Cola!”

It gave him zero information about his soulmate or when he would meet them. Not that he was concerned about the who, when, or where of it all. He wasn’t concerned about meeting his soulmate at all, in fact.

He wasn’t concerned about it even when his peers couldn’t seem to talk about anything else.
Even when they started finding their soulmates at school, in their clubs, or just in the city.
Even when he had a hard time falling asleep at night and the words on his chest would edge their way into his thoughts and he would unconsciously run his fingers over the skin where he knew they were without having to look.
Even when his best friend Taiju heard the words he had always longed to hear spoken to him by the sweet girl in the handicrafts club, Yuzuriha.
Even when his two best friends got a little more openly affectionate than usual when they were all hanging out.

Even when his two best friends felt the need to pester him about his seeming disinterest in soulmates in general, ignoring the fact that he was trying to dismiss the subject as he always did.

"I’m not concerned about finding my soulmate. It's probably the most unscientific thing in the universe and I'm not going to put a millimeter faith in some ridiculous thing like that.”

“Is that why you carry a bottle of cola with you all the time? For totally scientific reasons that have nothing to do with your soulmate?” Taiju teased him from where he was sitting with Yuzuriha in Senku’s lab, a safe distance away so as to not interfere with the experiment Senku was working on.

“No, that has nothing to do with my soulmate,” Senku responded in irritation, not looking away from what he was doing.

“Then why do you carry it around?” It was Yuzuriha who spoke this time with genuine curiosity in her tone.

“Because,” Senku paused, trying to formulate a reasonable response to the question that wouldn’t just raise more questions, “I happen to enjoy the... refreshing taste.” Taiju laughed and Senku finally looked up to see his two friends watching him with mirth sparkling in their eyes.

“I don’t think I’ve seen you drink a soda in all the years I’ve known you.” Senku put down the beaker he was holding with a heavy sigh.

“If I drink this whole thing right now, will you guys leave me alone?” Taiju and Yuzuriha shared a look before Taiju turned back to Senku. He nodded and gestured with his hand, obviously telling Senku to proceed. The young scientist shot them a glare with no real heat behind it as he unscrewed the lid off the soda. He pressed to bottle to his lips and started drinking, all the while trying to hold angry eye contact with his friends and ignoring their poorly hidden laughter.

Except Taiju had been right.
Senku hated soda. It was too sweet and felt weirdly heavy and thick and was just overall not appealing to him at all.

Senku had thought his pure determination would allow him to finish the bottle, but after just a few drinks he set the bottle back on the table, the sweet taste of the soda not enough to overpower the bitter taste of defeat.

At that point, Taiju was doubled over with laughter and Yuzuriha’s look of sympathy was ruined by her shoulders shaking as she valiantly attempted to hide her own laughter.

Why was he friends with them again?

Senku put on an exaggerated smile and gave them a thumbs up.

"Refreshing." Taiju's laughter grew even louder.

"You can just admit it's for your soulmate, Senku. We're not going to make fun of you or anything, you know," Yuzuriha assured him with a sweet, comforting smile. Senku rolled his eyes and turned back to refocus on his work.

"If that's what it was for, I would tell you. But it's not. So there's nothing to tell."

Yuzuriha shook her head and started talking about a project the handicrafts club was working on, leaving the subject of soulmates behind for the time being. But Senku couldn't help but keep noticing the half drank cola on the edge of the table out of the corner of his eye.

He really didn't carry a bottle with him all the time for his soulmate or anything. It was just…
He couldn't deny the fact that he would one day run into someone who happened to be really craving a bottle of cola…
So what was the harm in being prepared?


Even before his words appeared, Gen had been excited about the whole idea of meeting his soulmate. Of there being one person somewhere in the world that he was destined to meet and was destined to love.

As he grew up, his excitement didn't wane. The words on the inside of his arm just made him even more intrigued about the person he would eventually meet.

“I thought I’d seen your face somewhere before, Asagiri Gen.”

How were they going to know him before they ever exchanged words? Did they like Gen before they even met him? Did they hate him?

When his fame started to grow, interviewers, fans, and even random people would often ask him to share his words or talk about his soulmate. It was commonplace among celebrities to be asked these kinds of questions, considering how big of a role soulmates played in their society.

But the first time a fan asked, Gen felt something twist in his stomach. Why should this random person have the right to know something about him that he considered to be so important and so intimate? He had laughed awkwardly in response, noticeably uncomfortable, and had quickly given a flimsy excuse to leave the conversation as fast as possible.

After that, Gen took to wearing clothes with long sleeves that covered his words. Anytime an interviewer would ask about it, he would seamlessly diffuse the situation with a little humor and quickly turn the subject of conversation to his upcoming book or show.

When an interviewer once asked about why he never responded to questions about his words or soulmate, he just laughed and respond with "the people who need to know my words know them, and that's all that matters. Even if they don't actually know they know them yet!"

That got a laugh out of the interviewer and distracted them enough that they forgot their train of thought and move onto something else, and Gen got to keep his words a secret just a little bit longer. As his career continued and his fame grew, he still managed to keep his words something that only he and a select few people knew.

But just because he was adamant about not sharing his words with the world, didn’t mean his excitement about meeting his soulmate had died at all. If anything, it had continued to grow. He knew that every day, he was one day closer to meeting the mysterious stranger, his soulmate.

Each night, he would remove whatever long sleeved garment he had chosen that day and would carefully trace over the now overly-familiar words on his upper arm with careful attention. The action always filled him with giddy excitement and a little bit of hope for the future. When he was feeling especially down, he would spend long hours just tracing over them until he fell asleep to dream about a faceless stranger that he would love to the end of time.


In all of their thinking, or in Senku’s case definitely not thinking, about soulmates,
neither of them had considered the chance of a catastrophic world event getting in the way.


When Senku had first broken free of the stone, he hadn’t had time to stop and think about something like soulmates. So much had happened and now there was so much to do.

The most important being not dying.

The second most important being, again, not dying.

Third was actually getting stuff done.

Sometimes at night though, when he wasn’t so exhausted that he was asleep the moment he was horizontal, his tired mind would wander a little to the person who just wanted a bottle of soda that he would surely never meet.

It wasn’t until Taiju had also broken free of his own petrification and Senku had the help of a seemingly inexhaustible source of manpower that Senku had time to really think about anything, including the words that were still written on his chest, unchanged during the years of stone.

The two of them were sitting together around the fire as the sun began to set, Senku carefully roasting the fish that Taiju had caught earlier that day while Taiju enjoyed some well deserved rest.

Senku glanced over at his friend and caught him gently brushing his fingers over familiar words written on the inside of his forearm with a sad look. They’d been friends long enough that Senku knew what the words said without having to see them. He felt his chest tighten in sympathy.

Even before meeting Yuzuriha, the idea of soulmates had meant so much to Taiju. After hearing Yuzuriha say the words on his arm for the first time, Taiju had almost fainted from being overwhelmed with joy, and had definitely scared Yuzuriha a little with how loudly he had shouted in excitement. Senku couldn’t imagine what his friend was going through. To Taiju, it had to feel like he had more or less lost the love of his life.

“We’ll revive her,” Senku spoke up. Taiju's head snapped up at the sound of the other's voice. “We’re almost done with the revival solution and she’s the first person on our list.” He gave Taiju a small, reassuring smile which Taiju returned with his usual verve.

"I know! I'm just…" He looked down again and rubbed his forearm carefully. "I'm just very excited."

Senku smiled at his friend and unconsciously brought his hand up to scratch at his own words.

"Oh…" he heard Taiju breathe out. Senku looked up to see his friend's eyes full of sympathy. "I'm sorry, Senku. Here I am, talking about missing Yuzuriha when you're working so hard to revive her for me and you…" he trailed off, obviously unsure what to say. Senku shrugged and turned his focus back to the fire.

“It’s fine. I’m not exactly torn up about it or anything. You know how I felt about soulmates before the whole stone world thing happened.” He poked at the fire and told himself that his eyes were starting to burn because of the smoke. “I wasn’t worried about meeting them then and now I don’t even have to worry about it.” Senku shrugged. The fire popped and he jumped back a little to avoid the embers that shot out of it, rubbing his eyes under the guise of cleaning out some debris.

Taiju continued to watch him in silence for a moment. Senku stared resolutely at the fire, unwilling to acknowledge the sympathetic look his friend was giving him.

He wasn’t upset about the idea of not ever meeting his soulmate. In fact, it was better that way. He had a lot to do, what with saving the world and rebuilding society and all. He had plenty to focus on as it was.

If he felt bad for anyone, it was for the poor sucker who would never get that cola they wanted.


When Tsukasa depetrified Gen, he had tried to give him an overview of what had happened and what was happening to help the mentalist adjust to his new life faster.

Unfortunately, Gen was left with almost more questions than he had had when he originally woke up. Tsukasa and Hyoga didn’t seem interested in answering his incessant questioning, and anyone else he asked usually just shrugged or shook their head and said they didn’t know.

What caused the stone catastrophe?
Why was Tsukasa murdering people?
Were they going to get back to modern food at some point?
Who was this Senku character who had been able to keep track of the passing seconds for 3700 years so accurately that he knew the date when he had managed to break out of the stone all on his own?
Was anyone concerned about establishing doctors or anything?
Could he, for the love of god, get some clothes?
What had happened to his soulmate?
Was there still a chance he would meet them here in the stone world?

He knew it was probably pointless to keep hoping that he would find them. There was no way whatever force was behind soulmates would have been able to account for 3700 years of being petrified in stone. For all he knew, his soulmate had been turned into a statue and shattered by some force of nature before they ever got the chance to meet.

Deep down, though, he still held onto a tiny bit of hope that somehow, against all odds, he would meet someone in this strange stone world and the first words out of their mouth would be “I thought I’d seen your face somewhere before, Asagiri Gen.”


It hadn’t really dawned on Senku that the words written on his chest might be unusual in the eyes of the villagers. He hadn’t thought about it at all, actually, until they were all out in the river collecting iron.

He had shed his usual outfit to dive into the river and help with the search, baring his chest for the first time since he had arrived in the village. It didn’t take long for the ever-curious Chrome to start asking questions.

“Senku, what’s that written on your chest?”

Senku glanced down, barely able to catch a glimpse of the black script out of the corner of his eye.

“Oh, that’s just my soulmate mark.”

“Your what?”

“My soulmate mark.”

“I repeat. Your what?”

"My s-"

"I swear if you say soulmate mark like I know what that means, I'll throw this rock at you. I'm going to need more explanation." Senku glanced down again and scratched absentmindedly at the words.

"They're… Well they're supposed to be the first words that my soulmate would ever say to me."

"And your soulmate is…?" Chrome prompted.

"They're supposed to be this person that you're destined to be with," he paused for a second, trying to formulate the words. He'd grown up in a society where everyone knew about soulmates and they were such an integral part of life, he'd never actually had to explain the concept of soulmates to anyone before. "They're supposed to just be that person who's by your side and who loves you. They're just… your person. Not like in an ownership way, just… you know. A person. Who is… important to you. And there for you. No matter what. You both just… love and support one another. Or something. Yeah." He trailed off, hoping the others would accept his mediocre explanation and wouldn't push for more.

"So who's yours?" Suika piped up from the river bank.

"I'm not sure," Senku responded, scraping his nails across his collarbone enough to hurt. He rubbed the skin for a moment before dropping his hand back to his side. "I never met them." He heard Kohaku make a small sympathetic sound next to him.

"I'm sorry, Senku," she whispered. He gave her a small smile and a shrug.

"Not a big deal. There's bigger issues at hand."

"Isn't there a chance you can still meet them now, though?" Chrome asked. Senku shrugged and sniffed a little, quickly turning his attention back to poking around the water for iron.

"Probably not. The chances that they even survived the last 3700 years are insanely small, let alone that they survived, get revived, and I find them in my lifetime." Senku wiped some water from his eyes. It had probably splashed up when he had reached into the river with a little too much excitement. That had to be where it was from.

"Don't you want to meet them though?"

“Like I said, there’s bigger issues at hand than me finding some soulmate the universe assigned me.” He wiped his eyes again. He really needed to reach into the river more gently and stop splashing water on his face. Or something.


There was a lot going on around him, and the excited voices of the villagers started to overlap as Senku and his small science crew served up bowl after bowl of ramen.

He had his back to the crowd, focused on cooking the ramen, when one voice seemed to cut through the background noise.

"This seriously makes me wish I had something to drink…"

"Like cola," Senku whispered in unison with the unknown voice. He froze.

There was no way he had heard that right. No way he was about to meet his soulmate, the one he was supposed to meet some 3700 years ago, now, here in the stone world.

But then again, the fact that this stranger had said that sentence exactly had to mean something.

Senku was pulled out of his revery when the broth he had been carefully pouring overflowed and burnt his hand a little. He hissed a sharp breath and let the bowl clatter onto the table, sloshing broth and ramen all over it. He felt Kohaku nudge his shoulder to get his attention.

"Are you okay, Senku? I thought I heard someone I don't know say something over there," she pointed to a large rock a few feet away in the direction the voice had unmistakably come from, "and then you just froze up. Are they some friend of yours?" Senku shook his head slowly, not taking his eyes off the rock Kohaku had pointed at, trying to catch a glimpse of whoever was hiding behind it.

"No, he finally whispered in response. He cleared his throat and spoke a little louder. "I have no idea who that is." Kohaku nodded firmly and turned away from him.

"They might be a spy, then. We'll bring them out here and see what they want."

"Yeah, oka- wait what? Kohaku, wait, you can't do that I'm not-" Unfortunatlry for Senku, his words fell on deaf ears. The girl had already roped Kinrou and Ginrou into helping her 'smoke out the spy'.

He watched with anxiety as the three villagers crept closer to the rock, clearly ready to pounce.

Could this really be it? Was he really about to meet his soulmate?
Was his soulmate's first impression of him really going to be his friends threatening them at spearpoint?

He took a deep breath and tried to calm his now racing thoughts. There was no way that person was his soulmate. It was just one crazy coincidence he would laugh about with Taiju and Yuzuriha when they got reunited. He was ten billion percent sure that the man standing up from behind the rock with an overly innocent smile was-

Very, very pretty. Holy shit.

Maybe he should hold out hope that this man was his soulmate after all.

Kohaku, Ginrou, and Kinrou talked to the man for a bit while Senku continued to hide behind the little ramen cart and look at the newcomer.

While his expression was clearly exaggerated as he played the innocent, his eyes were sharp and calculating. The tell tale lines that marked him as someone who had been petrified ran down his cheek in a way that gave his overly bright smile a sharp edge.

That smile and asymmetrical haircut reminded Senku of someone he had seen before, but couldn't quite place. From somewhere in the far reaches of his memory, a sunny afternoon, Yuzuriha reading a dumb quiz, and the face of the rising star mentalist on the magazine cover came back to Senku in a rush. He studied the man standing with his friends, glancing warily at the spears still being pointed at him. Now that the memory had returned, there was no doubt in his mind that that was none other than Asagiri Gen, the hack mentalist who had been undeniably popular back in the old world.

"Senku, what do you think we should do?" Kohaku's voice pulled Senku back to reality and he realized he couldn't stay crouched behind a makeshift ramen cart staring at the man forever. He needed to know what business he had in the village and who had sent him.

He definitely, 100 percent did not need to know if he was his soulmate. That absolutely didn't even cross his mind for a nanosecond. This was all business.

He rose from his hiding spot, grimacing a little as his muscles complained about being crouched down for so long. He stepped out from behind the cart and crossed his arms, smirking confidently despite the fact that his mind was racing with questions and his heart was just, well, racing.

“I thought I’d seen your face before, Asagiri Gen.”


“Ah, nice to know I have fans even in this wor-” Gen cut himself off as the other’s words fully registered and everything else fell to the background. “I thought I’d seen your face-”

“What did you just say?” Gen asked, voice barely above a whisper, his eyes wide with shock. Before Senku could respond, Gen stepped forward and grabbed the scientist’s right arm, pulling it up and turning it over before dropping it and doing the same to the left. Senku pulled against him, trying and failing to break from Gen’s grip.

“Hey, what-”

“Where are they?” Gen cut Senku off, crouching down to look at Senku’s legs.

“Stop it! What the fuck are you-” Gen stepped back and aggressively pulled his left sleeve up to expose his upper arm where the words that Senku had just spoken were written in hurried but neat script.

“You know very well what the fuck I’m doing. Where the hell are your stupid words?” He watched as Senku hesitated for a minute. As Gen opened his mouth to pester the scientist even more, Senku reluctantly reached up and grabbed his collar, pulling it down to the side to reveal a small set of words that Gen recognized as his own from a few minutes before. Gen hesitantly stepped forward, reaching out to ever so slightly brush his fingertips against the words. He heard Senku suck in a sharp breath when his fingers made contact with his skin and dragged across it lightly.

Gen looked up in shock, vision warped slightly by the tears gathering in the corners of his eyes. Senku was chewing nervously on his bottom lip and resolutely avoiding eye contact, but otherwise his expression was unreadable.

“You… We…” Gen stuttered out in a hushed voice, not knowing what he was even saying. “Soulmates…”

At that word, Senku finally looked Gen in the eye for the first time since he had stood up from behind the cart. His expression was one of forced composure, but his eyes betrayed his nerves. Underneath it all, though, Gen could see a spark of excitement. Without thinking about what he was doing, Gen launched himself forward and threw his arms tightly around Senku’s neck. After a moment of hesitation, he felt Senku’s arms come up around his waist and pull him in closer.

“You’re real,” Gen whispered, not sure he had even spoken loud enough for the other to hear.

“As far as I’m aware, yes.”

“Shut up. I didn’t think… I mean I assumed with the end of the world and all…” he trailed off, too overcome with emotion to finish his thought. Gen rested his forehead against Senku’s shoulder and took a deep breath. “I’ve been waiting to meet you for so, so long.” He felt Senku stiffen for a fraction of a second before the scientist let out a long breath, his body relaxing and melting to press closer to Gen.


“Yeah,” Senku whispered, adjusting his hold around Gen’s waist to pull him closer and pressing his mouth to Gen’s shoulder. “So have I.”

He realized he had been. No matter how many times he told himself that soulmates were illogical and that he didn’t care whether he met his or not, deep down he had always been curious about who his was. He had always been excited to meet that one person who was meant for him. Deep down, he had always wanted what Taiju and Yuzuriha had.

He could hear his breath shaking as he pulled back from Gen just enough to look him in the eye, their faces still close enough that they were breathing the same air. If Senku had thought he was pretty when he first saw him from a distance, then Gen was breathtaking up close.

Senku reached up to tuck some of Gen’s longer white hair behind his ear, brushing his fingertips down his jaw before wrapping his hand around the back of Gen’s neck. Gen closed his eyes and made a content sound, a warm smile pulling at his lips. When he opened them again, his eyes were sparkling with unshed tears. Gen leaned in impossibly closer, their chests pressed tightly together.

“Senku?” The scientist’s breath caught in his throat at the sound of his soulmate saying his name for the first time.

“Yes, Asagiri Gen?” Gen’s expression shifted from one of excitement and contentment to a flat, unimpressed glare.

“Can you please not call me by my full name every time you say it?” Senku hummed and found he couldn’t stop his smile. He also found he didn’t actually want to.

“We’ll see. Anything else I can do for you, Asagiri Gen?” Gen rolled his eyes with a huff of laughter.

“Can I please kiss you?” In lieu of an actual response, Senku closed the already minimal space between them, pressing their lips together. At first, it was just a simple press of lips, both of them a little unsure and a little overwhelmed with emotion. But soon enough, they both relaxed into it. Senku’s hand at Gen’s waist flattened against his lower back and pressed them together firmly. Gen slipped one hand into Senku’s hair at the back of his head.

“I thought you said you didn’t know him,” Kohaku’s voice made Senku return to reality, jumping away from Gen just a little bit to look over at his friend.

“I don’t?” he asked more than stated. Next to him, still mostly wrapped in Senku’s arms, Gen started giggling. Senku nudged him with his hip, which just caused Gen to laugh harder and try to hide it by pressing his face into Senku’s shoulder. Kohaku just raised an eyebrow at the pair, looking skeptically at the space, or lack thereof, between them. Senku cleared his throat and looked anywhere but at his friend.

“He’s- This is- Well, apparently, he’s my… my soulmate.” Senku could feel the blood burning in his cheeks and hoped that it wasn’t as visible to everyone else as it probably was.

“Your wha- OH!” Her eyes widened and she looked at them both in excitement. “The words thing?”

“Yeah,” Senku nodded and chuckled, unconsciously tightening his arm around Gen’s waist, “the words thing.”

“That’s a pretty big thing, isn’t it?” Senku felt Gen nuzzle into his shoulder, nosing gently where his neck and shoulder met.

“Yeah,” Senku blushed and glanced at the other man out of the corner of his eye, his expression softening a little while he watched him. “Yeah, it kind of is.”

Gen peeked up at Senku out of the corner of his eye, smiling softly at him. Senku felt his chest tighten and his breath catch in his throat at the sight, overwhelmed by how cute and pretty the mentalist was. He couldn't resist once again wrapping his arms around Gen's waist and pulling him tight against his chest, burying his face into the mentalist's hair and taking a deep breath.

"It is," he murmured against Gen's hair, not sure if it was even loud enough for anyone but him to hear.

They stayed like that for a few minutes, too wrapped up in the feeling of finally having their soulmate there with them to care about the confusion and overlapping voices of the villages around them.

They'd both waited over 3700 years after all, Senku thought they'd earned the right to take a moment for themselves.

Eventually, Senku leaned back a little to be able to look at Gen more fully. The loose sleeves of Gen's overcoat had slid up a little in all the excitement and Senku could see the edge of black letters written on his inner arm.

Senku reached up and pushed Gen's sleeve up further, brushing his fingertips over the words. He quickly dipped his head down and pressed his lips lightly against the words before straightening back up. He reveled in the deep blush growing across Gen's cheekbones.

"I owe you a bottle of cola," Senku said quietly. Gen's smile grew and a small laugh escaped him.

"It's ok. It's not like there's a 7-11 right around the corner or anything."

"Sure, but don't forget, I'm a scientist. I can make you some." Gen's eyes widened and he leaned in for a kiss. He pulled back a fraction of an inch, staying close enough that his lips still brushed Senku's a little as he spoke.

"That might be the most romantic thing anyone's ever said to me."