When he woke, the stiff ache in the back of his neck woke before his brain did.
Rinto had slept slumped in his chair for almost an entire night. Half his body had gone numb, and the slightest movement made his joints crack as though he were about to fall apart. The desk lamp had long since gone out-not because the filament had burned out, but because his elbow had knocked the switch before he fell asleep. The entire laboratory was pitch-black, with only a little gray daylight filtering through the vent, too dim to even make out the balls of paper on the floor.
He sat dazed for a long while before raising a hand to rub his eyes. The scab on his fingertip caught on his eyelid and tugged with a piercing pain. He swore, "Fuck," braced himself against the desk, and stood. His numb legs sent him stumbling immediately, and his knee slammed into a desk leg. He grimaced in pain and took a long time to recover.
His throat felt as though someone had stuffed a handful of sand into it. He rummaged over the desk in the dark for ages without finding his water bottle, then kicked an empty bottle on the floor. Its clatter was especially jarring in the quiet room. Finally, he felt his way to the insulated jug Kabuto had left in the corner. He unscrewed it; the water inside had long since gone cold. Hugging the jug, he gulped down more than half its contents. The cold made his stomach clench sharply before his thirst finally eased.
The food box was still in the corner. He opened it to find rice balls as hard as rocks, squeezed one, then tossed it back. His stomach felt desperately empty, but he had little appetite. He pulled open a drawer and rummaged aimlessly until he found half a bag of soda crackers Kabuto had left earlier, all crushed to crumbs. He poured them into his palm and tipped the whole lot into his mouth. They were too dry to swallow, so he took another two gulps of cold water and choked into a fit of coughing.
Only after recovering for a long while did he switch on the desk lamp. The newly replaced bulb made him squint. As the light came on, the mess across the desk and floor hit his eyes: shattered iron fragments, crumpled balls of wastepaper, rock-hard rice-ball crumbs, and discarded engraving-blade tips scattered everywhere. He had no mind to clean up. His gaze went straight to the piece of three-nature starfall iron on the desk.
The residue problem that had held him up for almost a week was still unresolved. Switching had become smooth, but when the anchors reconstructed, the residual chakra in the corners of the channels wouldn't clear out. After enough switches, it either became too hot to hold or blew out outright.
He held the piece of iron and turned it over and over for a long time, muttering, "Fuck, the clearing circuit can't keep up with the reconstruction. By the time it's finished clearing, the new configuration is already built, and the residue's long since clogged the patterns..."
His earlier idea of lengthening the clearing circuit created an unusable amount of latency. As for simultaneous clearing, he simply couldn't nail the timing; the slightest error meant colliding chakra and a blowout. Every route was a dead end.
Irritated, he tossed the iron back onto the desk, grabbed a charcoal pencil, and scribbled on scrap paper. He sketched a structure that embedded the clearing anchors into the reconstruction nodes, but frowned after only a couple of strokes-the anchors themselves had to be dismantled and rebuilt. If he embedded the clearing structure in them, wouldn't it break apart along with them? Useless.
He crossed it out and started again, this time considering a tracking clearing structure that would move with the anchors' reconstruction. But as he drew, that felt wrong too. The structure was too dense. Engraved into starfall iron, the slightest deviation would make its parts interfere with one another. It would still blow up.
The more he drew, the more irritated he became. At last, he threw down the pencil, grabbed a piece of starfall iron, and decided to try a simplified interlocking anchor as a last-ditch attempt. He clicked it into the vise and fitted a fresh engraving tip. As he set the blade down, the cracks in his fingertips pulled painfully. He gritted his teeth, swore every time he cut something wrong, shook his hand for ages whenever it went numb, then kept engraving.
After nearly two hours of engraving, he finally finished. He took it to the steel target plate and tested it. On the first switch from Lava Release to Explosion Release, there was indeed a little less residue. But when he switched from Explosion Release to Lightning Release, the clearing anchors embedded in the nodes collapsed along with them. With a crack, a huge split opened in the side of the starfall iron. It nearly blew up right in his hand.
"Fuck!" He hurled the scrap iron hard onto the floor, scattering fragments everywhere. An entire morning's work, all wasted.
He tried two more versions in succession. They either failed to clear everything or blew up outright, adding almost half a box of scraps to the waste bin. The last blowout sent a fragment into his cheek, cutting another small wound. Blood dripped down his jawline. He wiped it carelessly, smearing blood and charcoal dust all over his face. His temper surged, and he slammed the engraving knife onto the desk, collapsed into his chair, and closed his eyes, unwilling to move.
As he sat there seething, someone knocked softly twice. It wasn't the cautious knocking from before, as though afraid of setting him off. The door pushed open immediately afterward, and Kabuto poked his head in, holding a stack of his own experiment records against his chest. He plainly hadn't come just to deliver things.
"Mr. Rinto, sorry to disturb you." Kabuto kept his voice very soft. "That little chakra-filtering configuration you sketched for me last week keeps leaking fluctuations around the edges when I use it. Could I trouble you to take a look? It should only need a couple of strokes. I won't take up much of your time."
Rinto raised his eyelids slightly and replied irritably, "Leave it there. I'll look when I have time."
"Ah, all right." Kabuto hurriedly set the small drawing on the clearest part of the desk, then placed the food box and fresh insulated jug he was carrying in the corner. "I brought you a bowl of hot ramen, fresh from the cafeteria. It's still hot. And you said you were running short on engraving tips, so I requisitioned a new box for you. I've put it over here."
He crouched down, swept the iron scraps and crumpled paper on the floor into a pile, and packed them into a garbage bag. He casually grumbled a little as he worked, not deliberately making a report, but more like venting in passing. "The Anbu are still at the entrance. Three came today, blocking the front gate. They even question the people delivering materials forever. The gatekeeper's about ready to argue with them."
"Those people from the research and development department downstairs haven't given up either. Yesterday they left materials and drawings in the gatehouse with your name on them. I sent them back and told them you didn't have time to see them."
Once Kabuto had mostly finished tidying, he glanced at the cut on Rinto's face and the blood seeping through the gauze on his fingertips. He set iodine disinfectant and fresh gauze beside the desk and said quietly, "You should disinfect that cut on your face. Don't let it get infected. The gauze on your hands needs changing too. It's gone hard as a shell."
Rinto didn't answer. He leaned against the chair back with his eyes closed and didn't move. Kabuto didn't dare say anything more. He picked up the garbage bag and quietly withdrew, closing the door without making a sound.
Only long after Kabuto had left did Rinto open his eyes. He glanced at the ramen in the corner, still steaming, but didn't touch it. His mind was full of the anchors that had just shattered. The more he thought about them, the more he felt his entire previous approach had been wrong, and the more irritated he became.
He didn't want to touch the engraving knife or draw any more plans. He got up and wandered aimlessly around the laboratory until he reached the materials rack, where he flipped through the towering stacks of discarded draft notebooks-not looking for inspiration, just too irritated to do anything but rummage.
Everything he turned up was junk from the past dozen-odd years: drafts of Wind Release configurations he had drawn when he first came to Konoha, dozens of ruined designs from explosions when he had first worked on solidifying senjutsu, and discarded notebooks from the Hashirama cells experiments. The drawings were a mess. Some pages had yellowed edges and were wrinkled from water damage.
He flipped through them one by one without any particular aim, occasionally swearing that he must have been out of his mind back then when he saw an especially ridiculous mistake. Eventually, he reached the battered notebook from the Hashirama cells experiments. A loose sheet was tucked inside, bearing a small structure he had casually doodled while drawing tracking anchors. Back then, to make the anchors follow cell growth, he had added a tiny "tail" to the end of each anchor that could bring stray chakra fragments back with it. In the end, he hadn't used it. He had simply drawn it and tucked it inside.
Rinto froze.
He held the wrinkled sheet and stared at it for nearly five minutes. All this time, he had stubbornly focused on building a separate clearing circuit that would sweep up the residue after the anchors had finished dismantling. But what if he added a little tail like this to the end of every reconstruction anchor? When the anchors dismantled, they could hook away the residual chakra in the corners along with them. There would be no need to wait until reconstruction finished before clearing. It would happen in sync with anchor dismantling, neither slowing the switches nor adding extra structures, and no residue would pile up in the patterns.
The moment that thought emerged, all his earlier irritation vanished. Clutching the sheet, he rushed back to the desk, grabbed the charcoal pencil, and began drawing on blank paper. He didn't even notice when he wore the point flat.
Rather than making a separate clearing circuit, he would break the clearing function into pieces and embed it directly into every reconstruction anchor. The instant an anchor dismantled, its tail would sweep away all the surrounding residual chakra. Once dismantling was done, the residue would be gone too. It would take no extra time, and there would be no problem with overcrowded structures.
As he drew, he kept muttering, "Fuck, why didn't I think of this before... Going to all that trouble to make a separate circuit, when I could've just divided the work among the anchors..."
Halfway through, he frowned again. If the anchors' tails were too long, they would slow reconstruction; too short, and they couldn't carry away the residue in the corners. He revised them again and again, adjusting the tails' length and angle seven or eight times. The paper was densely covered in drawings and corrections. To anyone else, it would have looked like meaningless scrawls.
By the time he had more or less refined the framework, it was completely dark outside. His stomach growled fiercely, and only then did he remember the ramen Kabuto had brought. He opened it to find that it had long since clumped together and gone cold. He didn't care. He shoveled down two mouthfuls, found the cold noodles hard to swallow, and gulped down some warm water. Then he pushed the bowl aside, grabbed a fresh piece of starfall iron, and clicked it into the vise.
He was especially careful when he set the blade down. At the end of every anchor, he had to engrave a tail structure as fine as a strand of hair, even more intricate than the previous three-nature configuration. A deviation of a single micron would render the tail useless, or even interfere with the anchor's reconstruction. After staying up all day, his vision had long since blurred. He would engrave for a while, close his eyes and rub them for ages, then bring his face so close to the iron that it almost touched. Partway through, his hand shook and he engraved an anchor wrong. He swore, threw away the half-finished piece outright, and started over with a new one.
By the time he finished the final stroke, the sky outside had turned pale with dawn. His hands were terribly stiff. He worked them for a long time, cracking his knuckles, before finally removing the starfall iron. He walked to the steel target plate, drew a deep breath, and injected chakra.
Lava Release-steady. Acid melted a deep pit into the steel plate, and the chakra flowed smoothly.
He switched to Explosion Release. The anchors reconstructed almost instantly, and the tails swept the residue away completely, leaving not a single fragment in the channels. The iron only grew slightly warm.
Then he switched to Lightning Release. Still smooth. No stalling, no residue. Lightning struck the steel plate and carved a deep gash.
Rinto's heartbeat quickened a little. He immediately began switching repeatedly: Lava Release → Explosion Release → Lightning Release → Lava Release. Back and forth, faster each time. After more than thirty consecutive switches, the starfall iron in his hand was merely warm. It hadn't grown hot or cracked, and none of the three natures had lost any power. The residue he previously couldn't clear was almost gone.
It worked?
He stopped, held the black iron, and stared blankly for two seconds. Then he tested it another dozen-odd times like a madman. It stayed steady every time. The knot that had trapped him for almost a week had actually come undone just like that, thanks to a discarded structure he had casually drawn more than half a year ago and forgotten himself.
He let out a breath and casually tossed the starfall iron onto the desk. All the strength drained from his body at once. Drowsiness and exhaustion washed over him like a tide, and his eyelids felt heavy as lead.
But after dozing for only two minutes, his eyes snapped open again, and he grabbed the drawing. During the tests, there had still been a trace of residue at the instant Lightning Release switched back to Lava Release. Though it didn't affect its use, it still wasn't right. Frowning, he wanted to adjust the tails' hooked angle again so they could bring out the fragments in even farther corners.
He had barely drawn two strokes before his hand shook so badly that he couldn't hold the pencil. He swore, "Fuck," and threw it down. He looked at the drawing on the desk, then at the successful piece of starfall iron. After agonizing for a long time, he finally decided to sleep first.
He didn't go lie on the bed in the inner room. He simply leaned back in his chair, pulled over the coat draped nearby, wrapped it around himself, and closed his eyes. Just as he did, he remembered the little filtering-configuration drawing Kabuto had left at the edge of the desk. He felt for it, squinted, casually corrected it with a couple of strokes, and tossed it back to the edge of the desk. Only then did he settle back again. Before long, his breathing deepened.
He fell asleep slumped in the chair like that, still clutching half a broken charcoal pencil. The drawings lay scattered in a mess across the desk, the bowl of clumped ramen sat to one side, and the successful piece of starfall iron rested quietly beside the drawings. Outside the window, it was already broad daylight. Faint voices drifted up from the research and development department downstairs, but he didn't wake. His brow remained furrowed, as though he were still wrestling with exploding anchors in his dreams.