He raises one finger.
Palms rise. The aisles accept the line like a throat that remembers how to swallow. Benches become walls again. Window rectangles stop pretending to be stepping stones and go back to being light.
"On three," Iruka says. "We walk the aisles and let the room be a room again. Palms visible. Ribs before shoulders. If you need to stop, you stop. Stopping is cheaper than clever."
Two fingers.
The class breathes in as one.
Three.
They move. Feet remember home. Shoulders remember not to brag. Iruka walks behind, close enough to own the weather and far enough to let it work.
"Pairs," he says. "Read your three lines while you walk. Words that make posture better stay. Words that make you louder go."
Shikadai and Naruto take the right lane."Feet are honest," Naruto says. "Shoulders get loud. Head is a leash.""Trim the last," Iruka says without looking. "Head chooses. Leashes embarrass."
Hinata and Izayoi move the left lane."Choose after first," Hinata reads. "Breathe before. Place ends.""Good," Iruka says. "Keep them small in your mouth so they stay small in your body."
A pair in the center says, "Hands honest. Ribs cheap. Stop early.""Better," Iruka says. "If you can say it while climbing a stair, it will work when the stair is rude."
Mizuki stands at the frame again, clipboard tucked, eyes polite. He does not write. He watches ankles, shoulders, and whether the room is learning how to own itself.
They loop once and return to the front board. Iruka lifts one hand and the room stops the way trained rooms do - no skids, no stumbles, no drama.
"Open demonstration," he says. "Two days from now. Parents watch. Doors, stairs, crowds. We will not perform. We will instruct. Two students assist."
Naruto's hand rises at a speed that tries to be legal. "Sensei," he says, and keeps his voice almost quiet. "Can I be with Izayoi."
Iruka does not say yes or no. He looks at Naruto's shoulders and then at the chalk door on the floor. He points to that small white rectangle by the teacher's desk.
"Eligibility is a drill," he says. "Three passes. First pass - you will be too loud on purpose and catch it. Second pass - you will be small. Third pass - if I can tell when you decide from across the room, the slot is Hinata's. If I cannot, the slot is yours. Izayoi anchors. Class watches feet and shoulders. Hinata gives one word at a time - no activation."
"Yes," Naruto says. It comes out like a vow he is scared to make loud.
"Izayoi," Iruka says.
"Here," Izayoi answers. He steps to the chalk door and stands a palm's width short of it, hands visible.
"Run one," Iruka says. "Make the error and buy it cheap."
Naruto approaches with his good ideas arranged in the wrong order. He reaches the door and tries to be narrow late. His shoulder announces a plan. Iruka says, "Stop," and the stop arrives like an apology that learned to be a decision. Naruto pays five - quick, clean - palms still up when he finishes.
"Again," Iruka says. "What did you buy."
"Cheap stop," Naruto says, breathing. "Next breath buys early."
"Better," Iruka says.
Mizuki tilts his head a degree. The clipboard remains quiet.
"Run two," Iruka says. "Small. Hinata - one word if it helps."
Naruto approaches again. Shikadai lifts two fingers where Naruto can see them. Palms up. Hands promise.
"Choose," Hinata says, soft.
Naruto narrows two heartbeats early. The chalk door fails to become a lesson. He passes.
"Thin," Hinata says, when his ribs pay and his shoulders do not.
Izayoi meets him on the far side, receives a near brush of sleeve with the politeness of an object that refuses to own another person's story, then steps through in turn and gives the chalk door nothing to remember.
"Place," Hinata says, last of her three words.
Iruka nods. "Better. Again," he says, and points at the real doorway toward the corridor, then back to the chalk door. "You will go chalk to chalk - three links - no sentences. Class will hold the aisles clear without becoming furniture."
The room adjusts itself by half inches. A pencil that thought about rolling gives up. A bag strap remembers which side of a desk it belongs to. The aisles become corridors on purpose.
Naruto steps to the chalk door. He glances at Izayoi and forces himself not to grin because grinning spends air. He narrows early - ribs first - then crosses the short gap and takes the second chalk at the board rail with the kind of modesty that fits in one finger of space. On the third link he feels pride arrive and pushes it down with a breath.
"Small," Hinata says for the last one.
Iruka's mouth does not smile because mouths do not have to do all the talking. "One more run," he says to Naruto, then to the class, "Watch what happens to ankles when heads decide too late."
He gestures, and a girl in the near row slides a chair foot a finger into the path without making it a test. Naruto sees it in time to prefer humility over speed. He stops for a thread of a beat, then goes. The chair learns nothing. The door is uninteresting. The class hears the lesson in how little they heard.
"Words," Iruka says, and means three.Naruto says, "Stop. Then small."Shikadai says, "Better. Again."
Iruka looks at Hinata. "Describe one thing without a sentence."
"Quiet," she says.
Iruka nods. "Run three begins now. No words. I must not see the decision arrive. If I do, Hinata takes the slot with Izayoi. If I do not, Naruto does. Class - eyes on feet and shoulders. Mizuki - you are furniture."
"Understood," Mizuki says, which is what furniture would say if it had paperwork.
Naruto breathes once like someone lowering a weight onto a shelf. He sets his palms where the room can see them. He walks.
Chalk door one: he becomes the version of himself that fits between two ideas and refuses to stand out. He passes.
Between doors: Izayoi crosses the flow the opposite way with the exact amount of attention a shadow deserves and not one gram more.
Chalk door two: Naruto almost lets his shoulder brag. The almost shrinks instead of growing. He passes.
Between doors again: a boy in the near row decides to pick up a pencil at the worst possible moment and then does not. The pencil stays where it is. Good culture corrects itself without speeches.
Chalk door three: Naruto's ankles tell the truth. His shoulders stop telling stories. His center stays small. He clears the frame and does not smile until he can afford it.
Iruka studies the aisle from the far wall to the near chalk, then the other way. He says nothing for the length of a breath that could be a decision.
"Again," he says.
Naruto blinks. "Again," he repeats, but at a whisper.
Iruka sets the stakes where they can be paid. "You will go once more for the room, not for the slot. Hinata, you will walk opposite him - no words. Izayoi, you will receive the worst idea the door can have without letting it become a story."
"Yes," Hinata says.
"Understood," Izayoi says.
They set. Palms visible. Aisles clear by consent. The chalk door at the board rail waits like a polite sore tooth.
"Begin," Iruka says.
Naruto and Hinata move at the same time toward opposite chalks and do not need to look at each other to avoid needing to. Their ankles tell each other the weather and their shoulders choose not to own. Izayoi makes the middle uninteresting. Both pass. The room hears the cost as zero.
"Eligibility," Iruka says then, because outcomes should belong to the rule. He points at Naruto. "You pass the quiet test if you can do it once more with me at the far wall not seeing the decision."
Naruto nods. He does not grin this time. He takes his place at the chalk and breathes where the end will be. Iruka walks to the far wall and becomes the kind of observer doors cannot perform for.
Mizuki shifts the clipboard under his arm and lets it be still. "For procedure," he says into the space between sentences, "parent committee will be briefed that Byakugan will not be activated. Safety only. Doors and stairs. Two students - names to follow." It is not a question. It is a log.
"Correct," Iruka says, without turning his head.
The room quiets so hard that the chalk can hear itself being chalk. Naruto lifts his palms two finger widths and freezes them there to promise. Hinata slides a chair foot back to base without sound so silence stays cheap. Izayoi marks the middle these drills deserve.
Iruka raises his hand for the last count of the morning. He does not hurry it. He does not make it heavy.
"On my word," he says. "If I can see the choice from across the room, the slot is Hinata's. If I cannot, the slot is Naruto's. Palms where I can see them. Ankles honest. Ribs before shoulders. Begin on three."
One.
Naruto's breath lands where it will end.
Two.
Hinata's shoulders choose not to announce comfort.
Three.
Iruka's hand cuts the air.