It started with an itch.
Not a metaphorical one.
An actual, specific, maddening itch, somewhere on his left shoulder blade, in the exact spot his right hand couldn’t reach no matter how he twisted.
He tried anyway — arm over the shoulder, arm up from below, back against the doorframe — and failed every way a person could fail at something this small and this stupid, until he gave up and stood there breathing hard, furious at an itch.
That was the moment, more than any of the others, that made him start thinking about it seriously.
Not a sword.
Not a weapon.
He wasn’t sitting in a prison cell dreaming about cutting people in half — that thought, when it surfaced at all, felt distant and unearned, like planning a parade before he’d won anything.
What he actually wanted was smaller and, somehow, more humiliating to admit: he wanted to carry a bucket without thinking about it.
He wanted to brace himself against a wall without recalculating his balance first.
He wanted to scratch his own back.
He wanted, more than anything, to stop being reminded every single hour that something was missing.
That was when the memory surfaced — not summoned, just arriving, the way memories from before tended to arrive lately, uninvited and a little unreal, like footage of someone else’s life.
Shanks, still captaining a crew years after the sea had taken his arm, like it had simply never occurred to him that it should slow him down.
Eustass Kid, who hadn’t waited around feeling sorry for himself — he’d just built a new one and dared the world to say something about it.
Even Sasuke, eventually, in the part of the story Ren remembered least clearly.
There used to be a joke about it, some half-serious internet bit about a club nobody applied to join.
Ren had never expected to qualify.
Underneath all of it, though, was the one that actually mattered — not for the joke, but for the mechanics.
A swordsman, fictional, half-remembered, from a game he’d sunk absurd hours into in a life that increasingly felt like a rumor: Sekiro, who had fought, and climbed, and lived, with an arm made of wood and metal and clever hinges instead of flesh.
Ren looked down at his shoulder.
Why can’t I make one?
The thought lasted exactly as long as it took reality to answer it.
He had no workshop.
No proper tools.
No modern materials, no bearings, no electronics, no idea, really, how a human shoulder was even supposed to interface with something that wasn’t attached by nerves and bone.
He wasn’t going to build Sekiro’s prosthetic.
That thing didn’t exist here and never would, not from him, not like this.
But the game hadn’t invented the idea of a mechanical arm.
It had just been the version of the idea Ren happened to remember.
The actual concept — a rigid structure, strapped and hinged, doing a smaller job than a real arm but doing something — that part wasn’t science fiction.
That part was just carpentry with better ambitions.
I don’t need to build the final version, he thought.
I just need to build the first one.
He found Jiro in the yard and asked without preamble.
“Where do they make things?
Fix things?”
“Workshop.”
“Can I go?”
Jiro didn’t answer right away, which Ren had learned by now meant the question underneath the question was still being weighed.
“Why?”
Ren looked at his shoulder instead of at Jiro.
“I need to try something.”
“Try what?”
He hesitated, and then just said it.
“A prosthetic.
Not a good one.
Just — something.”
Jiro’s expression didn’t change, but something behind it did.
“You understand you’re not getting your old arm back.”
“I know.”
“And a wooden arm won’t make you whole.”
Ren paused at that — not because it stung less than he expected, but because it stung in a way he’d already made peace with, somewhere between the nightmare and the bucket and the itch he couldn’t reach.
“I know that too.”
“Then why?”
“I just want to see what I can do.”
That, apparently, was the correct answer.
Jiro looked at him a moment longer, the way he looked at a stance before correcting it, and then he stood.
The workshop smelled like sawdust and hot metal, and it was louder than Ren expected — hammering somewhere, the scrape of a plane, someone arguing quietly over the price of a repair.
Jiro led him in, said something to a guard Ren didn’t catch, and left him at the edge of a workbench occupied by a wiry man with permanently narrowed eyes and hands covered in small, precise scars.
Ren picked up a metal fitting to look at it.
“Don’t.”
He put it down.
Looked at something else.
Picked that up too.
“I said don’t.”
“I’m looking.”
“With your hands.”
“They’re connected to my eyes.”
The man — Takeshi, Ren would learn, though not from any introduction, just from someone shouting the name across the room later — looked at him slowly, the particular look of a person recalculating how much of his day this was going to cost him.
“You’re annoying.”
“I’ve been told.”
Takeshi went back to his work without another word, which Ren decided, on reflection, was not actually a dismissal.
Nobody had told him to leave.
He tried to help.
That went badly.
He picked up a length of wood to hold it steady for a cut, and the moment Takeshi’s hand let go to reach for the saw, the wood twisted under Ren’s one-handed grip and slid clean off the bench, and Takeshi caught it an inch before it hit the floor with the weary reflexes of a man who had apparently already guessed how this would go.
“Sit somewhere else.”
“I can help.”
“You can help by sitting somewhere else.”
Ren sat somewhere else.
He watched instead — the way he’d learned to watch Jiro — and after a while he stopped watching the wood and started watching Takeshi’s hands, the small adjustments, the way he braced things against his own body when he needed a second grip and didn’t have one free.
That, Ren noticed with sudden interest, wasn’t so different from his own problem.
Takeshi had two hands.
He just didn’t always have two hands free.
And then, uninvited again, another memory surfaced — not a game this time, not a character.
A documentary, or something like one, watched half-attentively in a life he could barely call his own anymore: a man with no arms at all, eating with a fork gripped between his toes, turning the pages of a book the same way, writing his own name with a pen held between two toes, in letters steadier than most people managed with fingers.
Ren remembered being mildly impressed by it at the time, in the disinterested way a person is impressed by something that will obviously never apply to them.
He looked down at his own two feet, planted uselessly on the workshop floor while the rest of him failed at basic carpentry.
Obviously never apply to me, he thought.
Sure.
He didn’t say anything about it.
He simply sat down properly on the floor next time — ignoring the look Takeshi gave him for it — braced a scrap of wood between his foot and the leg of the bench, and held it steady while he worked at it one-handed from above.
It wasn’t elegant.
His balance was wrong for it at first, and his ankle cramped up faster than he expected anything that far from his shoulder to complain about a shoulder problem.
But the wood held still, which was the entire point, and holding still was something his hand alone had never quite managed to do.
Takeshi glanced over eventually, taking in the arrangement — a boy sitting cross-legged on his workshop floor, gripping a piece of wood with his foot like it was the most reasonable thing in the world.
“What are you doing.”
“Adapting.”
“With your foot.”
“You have a better idea?”
Takeshi looked at the foot.
Then at the wood, which was, undeniably, holding still.
He didn’t have a better idea, and to his credit, he didn’t pretend to.
“Don’t do that near the saw.”
“That was already the plan.”
He kept doing it anyway — carefully, well clear of anything with an edge — and it became, without either of them ever formally deciding so, simply another tool in the very short list of tools Ren actually had.
Not a trick.
Not a party skill.
Just one more thing his body could do that it hadn’t been able to do a season ago.
He came back the next day, and asked for scrap wood instead of tools, and Takeshi, without looking up, told him where the offcuts were kept.
His first project was not a prosthetic.
His first project, if he was being completely honest with himself, was the itch.
It took him less than an hour: a thin offcut, whittled down one-handed with a knife Takeshi handed him without comment, a few notches carved crosswise at the tip, no straps, no joints, nothing that had any business being complicated.
He reached it up and over his shoulder, found the spot, and dragged the notched end across it.
Ren went very still, eyes closed, wearing an expression of such profound and undignified relief that Takeshi actually looked up from his own work to see what had happened.
“What is that.”
“A back scratcher.”
Takeshi looked at the stick.
Then at Ren’s face, which had not yet returned to a normal configuration.
“That’s a stick.”
“It’s a precision instrument.”
“It’s a stick with notches in it.”
“It’s a precision instrument,” Ren said again, with the calm certainty of a man who had just ended a three-week war, “that has changed my life.”
Takeshi didn’t smile, but he made a small sound that might have been the ancestor of one, and went back to his bench, and didn’t tell Ren to sit somewhere else for the rest of the afternoon.
It was, by any honest measure, a stupid little thing.
It was also the first object Ren had built with his own hand that had done exactly what he needed it to do, on the first try, with no argument.
He decided, somewhat giddily, that this counted as engineering.
If this counted, then the actual project — the harder one, the one that mattered — was just a bigger version of the same idea.
Notch the wood until it did what a body needed it to do.
Emboldened by precisely one stick, Ren decided his second project should be considerably more ambitious.
That went worse.
The first attempt was — there was no generous way to describe it.
A length of wood, a strap cut from an old bit of leather, a joint that was meant to bend at something like an elbow and instead simply didn’t bend at all.
He strapped it to his shoulder and stood there wearing it like a very stupid trophy.
Takeshi glanced over eventually.
“What is that.”
“A prosthetic.”
“That’s a chair leg.”
“It’s a prototype.”
“It’s a chair leg.”
Ren looked down at it for a long moment.
“…It’s a prototype made from a chair leg.”
Takeshi didn’t laugh, exactly, but something in his face moved in the direction of laughing and then thought better of it.
The second attempt balanced worse than the first.
The third had a joint that worked, briefly, and then didn’t, and pinched him hard enough to leave a mark.
The fourth fell apart entirely the first time he tried to lean on it, and he ended up on the workshop floor with a broken chair leg strapped to his shoulder and sawdust in his hair, and for one long, undignified moment he considered simply staying down there.
Takeshi’s shadow fell over him.
“Get up.”
“I’m resting.”
“You’re sulking.”
“Strategically.”
Takeshi held out a hand — not sympathy, just logistics, a way to get a small idiot off his workshop floor faster — and Ren took it and got up.
He didn’t ask for help again.
He didn’t need to, not directly; Takeshi started correcting him without being asked, a word here, a gesture there, your joint’s in the wrong place, wood splits along the grain not across it, you’re bracing it wrong.
None of it was instruction, exactly.
It was closer to a man unable to keep watching something be done badly without saying something.
Ren understood by now that this was probably as close to being welcomed as Takeshi’s workshop ever got.
Prison kept happening around all of it.
Some days there was no workshop time at all — he was hauling supplies, or scrubbing a corridor, or peeling something unidentifiable in the kitchen while an older prisoner explained, unprompted, exactly how much salt was too much salt.
The lessons didn’t arrive on a schedule.
They arrived in the cracks between everything else, which was, Ren was beginning to suspect, the only way anything real ever got taught to anyone.
He still hadn’t stopped watching Jiro either, on the evenings there was enough light left for it.
Jiro still hadn’t offered anything more than that.
But somewhere in the last few weeks Ren had started running through the shapes on his own afterward, alone in a corner of the yard with a stick that wasn’t a practice sword, badly, his balance arguing with him at every turn his body used to know without thinking.
Nobody had told him to.
Nobody had told him not to, either, which in this prison had started to feel like the same thing as permission.
Hanako’s shelf of names hadn’t gone anywhere either — he ran through the first dozen in his head sometimes while he swept, mostly getting them wrong, which she seemed to find less annoying than he expected.
By the end of that stretch, he still didn’t have a working prosthetic.
He had a small, growing pile of failures, each one slightly less embarrassing than the last, and a workshop that had stopped telling him to sit somewhere else.
That, for now, would have to count as progress.