Chapter Text
Senku first met Kohaku the way he’d met everyone else in his life: in monochrome.
That was how he first saw the new world, the statues, Tsukasa, Ishigami village, all of it. In a series of greys which he knew in theory were colourful, but had no way of comprehending as such.
Senku paid it no mind. After a lifetime of experiencing the world as such, one got used to these things. Besides, Kohaku herself was sure to be almost the same.
They reached the village without it coming up. He met Ginro and Kinro without it coming up either.
It wasn’t until Chrome showed up that it was mentioned at all.
Chrome seemed enthusiastic and, despite an apparent lack of common sense, Senku suspected that it belied a genuine intelligence to rival his own. He was happy to indulge him in a ‘sorcery battle’ or whatever, if only for the amusement.
Chrome was standing over the fire he’d created, waving his hands around it, putting on a show. The theatrics were more than over the top, but at least the other three seemed into it.
“Behold! My bad sorcery!” Chrome announced, reaching into a small pouch on his belt and pulling out some sort of powder. “Rainbow bridge! Watch as I manipulate fire!”
Senku couldn’t have seen its full effect, naturally, but he knew what it meant.
The rest of the audience wasn’t quite as intrigued as Senku though.
“What was that supposed to be?” Ginro asked, leaning against his spear. “Nothing happened.”
“What do you mean nothing happened! How about this then.”
He threw another powder on. Senku didn’t miss the way the flames turned a darker shade of grey for a moment.
“Oh,” Kohaku exclaimed. “The fire’s changing colour!”
“Yes, finally .” Chrome rolled his eyes. “At least one of you appreciates my genius.” He grinned maniacally as he pulled another grey power from his pocket. “Now behold true sorcery!”
Kohaku stayed his hand. “Chrome, you’re the only one getting the full experience.”
“Eh?”
“Or so I assume.” She paused to look over at Senku. He nodded.
Chrome huffed and pouted, but moved onto his next tricks, which notably didn’t rely on colour to be impressive.
This all made things much more interesting. Between his storehouse and colour-sight, Chrome was proving to be more useful with every second.
Leaving behind Taiju and Yuzuriha had been a tragedy not just for the loss of them as people Senku cared about, but also as his colour spotters.
Being soulmates with one another, they’d had the full spectrum at their mercy for years before the petrification, and Taiju had proven invaluable since waking up. Even before, one of the reasons he’d been so eager to keep Taiju around was for how useful a pair of colour-seeing eyes could be.
But now he had a suitable replacement.
It was easy to bring Chrome into his plans. He was excited to help, and had a personal stake in the matter. But Senku didn’t bring up his colour-sight until the following night.
“So, Chrome, you’ve met your soulmate.”
Chrome nodded. “Heck yeah.”
While Chrome was obviously eager to talk about it, Kohaku groaned. “Can we please not talk about that?”
Chrome snickered. “She thinks it’s gross that her sister’s my soulmate.”
“That Ruri person, right?”
“Yep!”
“I said please.”
That explained a lot. Chrome devoting his life to trying to save his soulmate, while not something Senku could personally relate to, was something he understood.
“Whatever we think of it, that colour-sight of yours is going to be invaluable in making antibiotics. I could get it done without your help, but it’ll make the process a lot easier.”
“Baaad!”
“If it helps Ruri…” Kohaku shook her head and sighed.
“You’re just jealous you don’t have colour-sight.” Chrome smirked.
“Seeing blue is enough.”
“Still not as good as seeing all of them.”
Kohaku rolled her eyes before turning back to Senku.
“What about you?”
Senku raised an eyebrow. “What about me?”
“Your colour. Which do you see?”
There it was. Senku had hoped the conversation might avoid this point. They would have found out eventually though, he supposed it was better to get it over with.
“I don’t see any colours. Just grey.”
Chrome and Kohaku didn’t reply immediately, but Senku could feel them staring at him. Senku wasn’t ashamed of it or anything, far from it. He was comfortable seeing in monochrome, he’d never known anything different after all. But talking about it forced him to face the consequence of not having a colour.
“Oh Senku…” Kohaku’s voice was soft with pity.
“It doesn’t necessarily mean I don’t have a soulmate,” he clarified. “Before the petrification there were people with grey eyes. It was rare, but normal. But yes, there’s always the possibility…”
The way they were looking at him made Senku’s fidgeting all that much worse. It always went this way, even when he had told Taiju.
“It doesn’t bother me,” Senku said, perhaps a little too defensively. “Soulmates are illogical and unscientific. Plenty of people never meet their soulmates, and plenty more have found that kind of connection in people who aren’t theirs.” His throat felt uncomfortably dry.
From the way that Kohaku and Chrome were looking at him, Senku didn’t think they believed him.
“Whether I have a soulmate or not, it doesn’t matter now anyway, does it? Whoever they are, they’re probably still petrified.” Senku had already had this conversation with Taiju, but it didn’t keep it from stinging. Never meeting your soulmate and not having one in the first place were two very different things.
It didn’t take long for them to change the subject. All three of them were deeply uncomfortable, and asking more questions about the way the world worked seemed a much more pleasant way to waste the rest of the evening.
Meeting Asagiri Gen for the first time had been… a strange experience, to say the least.
Aside from his bizarre hair and the crack scarring his face that marked him out from the villagers, Senku had deemed him relatively unremarkable. He only knew of Gen in passing and, while winning him over was a matter of life and death, Gen was little more than a road block.
However, as the day went on, he was surprised by just how easy it was to be around Gen. How much he enjoyed being in the man’s presence.
It was different to how he felt around Kohaku, Chrome and Suika. He enjoyed their company too, being around them was relaxing, and they were friendly and enthusiastic. Despite only knowing them for a few weeks, Senku was already confident that they would prove to be loyal allies and good friends.
But that paled in comparison to the warmth and comfort he felt just standing next to Gen. Which, of course, was disturbing: Gen was immediately untrustworthy, by all definitions he was the enemy, and yet Senku couldn’t help but feel overwhelmingly safe around him.
Senku spent as much of the day on building the generator as he did showing off. He needed to bring Gen onto their side, so he could probably justify it if he tried, but he wasn’t so stupid as to ignore the immense gratification he received at Gen’s shock and awe.
He wouldn’t figure out what was wrong with him until later that night though.
Finding anyone bleeding out on the forest floor would be distressing. But for some reason, when Senku saw Gen lying in the grass, unconscious and bloody, it struck a chord of anger in him he didn’t even know existed.
After instructing Kohaku to carry Gen back to the hut, Senku hurried ahead, trying to push these foreign emotions down to make room to perform first aid.
He was already tearing up whatever spare fabric he could find into strips when Kohaku lowered Gen onto the floor and applied pressure to the wound. When he had enough, Senku knelt down and leant over to start wrapping the makeshift bandages around the wounds.
He stopped the second his hand brushed against Gen’s torso.
As soon as he did, the grey disappeared.
Seeing colour for the first time was nothing like he’d been told it would be. People spoke of the world ‘blossoming’ into colour, of the grey leaking out of it, leaving only vibrancy behind. But for Senku, one second, he was seeing in grey, and with a flash it was all gone, leaving him dazed and staring down at Gen’s chest, slick with a mix of real and fake blood.
The colour was so vibrant it made him dizzy.
“Senku?” Kohaku said with a harsh urgency. “What’s wrong?”
Senku took a breath, blinked, and then set about his job. “Nothing. Chrome, find the poppy seeds, the big ones, and scrape out the insides.”
Chrome did as he was told but Senku took no notice. He was thankful for how surprisingly minor the wound was, most of the bright liquid soaked into Gen’s clothes appeared to be a blood substitute, and the bleeding, while not insubstantial, was manageable. Senku had him patched up in a minute or so, no stitches required, and all that was left was to finish his painkillers and clean up the mess.
Once he’d calmed down and the adrenaline had left his system, getting on with the clean-up proved to be more difficult than he thought it would be.
The world in colour was so drastically different from the world in monochrome and he found himself constantly distracted by it all.
All of his materials looked different in colour, and he would have struggled to figure out what was what if he hadn’t already had Chrome help him label everything. He looked through them, piecing together a mental map of what colour was what based on what he knew about the different minerals.
He might have asked Chrome to help if he was awake, but he’d nodded off in the corner. Then again, explaining it all would have been inconvenient, so maybe keeping this to himself for the time being would be a good idea.
This whole soulmate business was confusing after all, and Senku had been half convinced he didn’t have one for the best part of his life. He wanted to sort it out in his own head before talking to anyone else about it.
A few hours later, still unable to sleep, Senku heard shuffling. He turned around to find Gen stirring.
His breath hitched and he watched, apprehensive, waiting for Gen’s reaction. But nothing of the sort came. Gen began to mumble and Senku listened to his request and watched him. He saw Gen’s eyes, glazed over, not seeing anything, and Senku let out a breath he didn’t know he’d been holding.
He agreed to Gen’s request. For something as small as cola, Senku wouldn’t have dreamed of refusing him. At that point, Senku wasn’t sure he’d be willing to refuse Gen anything, and he still didn’t know what to make of that.
Gen shortly drifted off again and it wasn’t long before Senku found himself succumbing to sleep too.
When he woke up to find Gen gone, he wasn’t surprised. They all knew that if Gen didn’t get back to the Kingdom of Might soon, they’d all be doomed.
Senku may not have been surprised but he was disappointed. He supposed their conversation would have to wait until the next time they met, whenever that would be.