Before the preparatory class on the Transformation Technique began, Mine brought in an old mirror.
The mirror was small, with burn marks on the frame and a chip missing from the lower right corner. When it was placed at the front of the temporary classroom, the children all fell quiet for a moment. Not many things had survived the disaster intact. An object like a mirror, one that reflected faces, somehow made them more uneasy than wooden desks or bowls of water.
Kiyo asked softly, "Are we looking at our faces today?"
Che looked at his slightly crooked reflection in the mirror. "Or maybe it'll show who didn't wake up properly this morning."
Kiyo immediately touched his face.
Saori sat nearby with her rag doll in her arms, one hand holding down its bell. She did not look at the mirror. Instead, she looked at the doll's face, as if the expression stitched from cloth felt safer.
Mine tapped the wooden board. "Today, we're discussing the Transformation Technique. We're still only watching, not practicing."
After saying that, she looked at Che.
Che raised his hand. "I've already learned to reflect before being reminded."
"I hope you truly have," Mine said.
The Transformation Technique was different from the Clone Technique. The Clone Technique created phantom images outside the user's body, while the Transformation Technique covered one's own appearance with another form. Mine did not rush to form hand seals. Instead, she had the children stand before the mirror one by one and name the feature on their face that people would recognize most easily.
The older children said their eyes.
Kiyo said his forehead cloth.
Mine reminded him, "Forehead cloth isn't part of your face."
Kiyo thought about it seriously. "Then it's my nose."
Che murmured, "Congratulations on discovering a core facial component."
Mine's gaze swept over him, and he immediately shut his mouth.
When it was Saori's turn, she stood before the mirror for a long time before quietly saying, "My mouth."
"Why?" Mine asked.
"I don't talk much," Saori said. "So when I open my mouth, people look."
The classroom fell silent.
Che looked at her, and something stirred gently within him. Saori truly did not say much normally. Her presence was often hidden behind her rag doll and bell. But she knew when people looked at her, and she knew her silence itself could become a defining trait.
When it was Che's turn, he stepped before the mirror.
The child in the reflection looked thinner than he had thought, but his eyes were too alert. A four-year-old's eyes should not always look as if they were taking notes. Che stared at the mirror and suddenly understood a little why Mine had made them look at their faces before teaching the Transformation Technique.
Before becoming someone else, first learn what made you yourself.
"What about me?" Mine asked.
Che wanted to say her eyes, because he always felt his own gaze was not hidden well enough. But admitting that outright was too dangerous. So he said, "Your expression."
"What expression?"
"Like you're about to make me copy something ten times."
Kiyo snorted with laughter.
Mine did not punish him. She only said, "That is a trait too. A person's appearance is not limited to their eyes, nose, and mouth. Posture, habits, expressions, speaking rhythm—all of those count."
She walked to the mirror and formed hand seals. Dog, Boar, Ram.
Chakra rose from the surface of her body like a thin layer of clothing. As the white smoke dispersed, Mine transformed into Nao.
Kiyo's eyes went wide at once. "Auntie Nao!"
Che did not speak immediately.
The outward appearance was very close. The hairstyle, clothes, height, and facial contours were all right. But the posture was wrong. When Nao stood, her shoulders lowered slightly, as if she were always ready to bend down and check a child's wounds. The Nao Mine had transformed into stood straighter, and her gaze was more like a teacher's.
Saori said softly, "That isn't Auntie Nao."
Mine looked at her. "What doesn't match?"
"She wouldn't look at us like that."
Che made a mental note about Saori: she did not judge people by their faces alone.
Mine released the Transformation Technique, and the white smoke dispersed. She nodded. "Very good. The Transformation Technique does not end with changing your face. If you transform into someone without understanding how they stand, speak, or remain silent, it will be easy to give yourself away."
Che listened intently.
Mine did not immediately have them sit down. Instead, she turned the old mirror at an angle, letting the light from the window fall slantwise across its surface. The reflections inside stretched a little longer. Standing beside it, the children could see their own faces as well as the shoulders of others behind them. In that moment, the mirror no longer looked like a mirror. It looked more like a cold surface of water that forced every detail into view.
"Now for the second thing," Mine said. "Pair up and observe each other. You may not say whether someone is pretty or not. You may only describe traits."
Kiyo immediately looked at Che. "Then can I say your eyes are too scary?"
Che smiled. "You can, but I'll also honestly say your forehead is perfect for sticking punishment notices on."
Kiyo covered his forehead, feeling that this observation exercise had already lost all fairness.
In the end, Mine separated them herself. Che was paired with an older child named Kohei. He had a faint mole on his face and always liked to purse his lips before speaking. Kohei clearly did not want to be paired with an Uchiha orphan, standing half a step farther away than required. Che did not point it out. He simply remembered that half-step.
"You go first," Kohei said.
"You put more weight on your left foot," Che replied. "You purse your lips before speaking, and your right index finger likes to rub against your sleeve cuff. The faint mole isn't the most obvious feature, because you care about it too much, so people notice your hand first."
Kohei froze, his face slowly flushing red. "Why are you looking at so much?"
That drew the attention of several children nearby.
Che's heart tightened. He had gotten carried away. Observing came as naturally to him as breathing, but to others, being broken down into one trait after another was uncomfortable. Talent without restraint became pressure. When he saw Kohei hide his right hand behind his back, he realized he had already embarrassed him.
He lowered his voice. "Sorry. I said too much."
Kohei did not respond.
Mine walked over without criticizing him right away. She looked at Kohei first. "You describe Che."
Kohei held it in for a while. "He... talks like an adult. His eyes always look like they're searching for mistakes. His shoulders don't move much when he stands."
Kiyo added from the side, "And his mouth is really annoying."
Che looked at him. "Thank you for providing this folk data."
Mine lightly tapped the wooden board against her palm. "Remember this feeling. Observation is not about taking people apart for your own use. If the Transformation Technique becomes nothing but exploitation, you will become less and less like a person. A ninja must see details, but they must also know whether their gaze hurts the person they are watching."
Those words were like a thin needle piercing Che's habit of recording everything.
He remembered the pages he had written during this time: Kiyo was impulsive, Saori was quiet, Nao was steady, Sosuke was hard, Sae seemed like the kind of person who could make paper bite. Every detail was useful, but if he regarded them only as "useful traits," how would that make him any different from those cold, impersonal files he feared?
Kohei did not speak again afterward, but before class ended, he tugged his sleeve cuff down and still returned to the line. Che did not stare at his hand again. When Mine asked them to repeat what they had learned, he only said, "Observation should leave room."
Mine glanced at him. "That is more important than everything you said before."
This technique would be far too useful in the future. Infiltration, escape, misdirecting attention, creating differences in identity—all of it could use the Transformation Technique. But it was more complicated than it looked. Transforming into another person was not merely about covering oneself in chakra. It also required understanding that person's habits.
In other words, observing people was itself the foundation of the Transformation Technique.
And he had always been observing.
That realization made him wary.
After class, Mine had everyone write three sentences: their own defining traits, the things others were likely to mistake about them, and the limitation they had learned today.
Kiyo wrote: "I have a nose. Other people have noses too. So you can't only look at noses."
Che stared at it in silence for a long time. "This is simple, but not lacking in philosophical depth."
Saori wrote: "The bell is not a face, but people will remember it."
Che wrote: "Expressions are traits too. Transformation requires learning posture and speech. Looking alike does not mean being real."
Mine paused when she saw the last sentence. "That's very good."
Che lowered his head. "I saw it in the mirror."
"Then remember it."
Che had thought the lesson was over, but after Mine collected their sheets, she picked up the old mirror again.
"One last look," she said. "Not to see whether you look like a ninja, but to see whether you missed anything today."
The children lined up and passed by the mirror. As Kiyo went by, he deliberately puffed up his cheeks, as though trying to rescue his nose from being a "core facial component." When Saori passed it, she held up her rag doll to the mirror so it could have a look too. When it was Che's turn, he saw that the corner of his mouth still held the curve of a joke, but his eyes were not smiling with it.
He suddenly understood that his problem was not simply being too alert.
He was too used to hiding tension beneath ease. What others heard was a joke. What the mirror saw was vigilance.
Mine spoke quietly beside him. "A mirror won't tell on you, but it won't hide things for you either."
Che did not talk back.
Normally, he probably would have said something like, "Then I'll look in mirrors less often." But this time, he merely nodded. Because he knew Mine was not trying to frighten him. She was placing the most basic and troublesome thing for a ninja before him: you could deceive your enemies, but you could not deceive yourself forever.
That night, Che made his private notes more detailed:
"Transformation Technique: chakra coating, appearance imitation, detail maintenance, behavioral disguise."
"The difficulty lies not only in the technique, but in observing the target."
"Risk: I am used to observing people. I may be naturally suited for it, but that also makes me easier to expose."
After writing that, he stopped.
His reflection in the mirror surfaced in his mind again.
Eyes too alert, reactions too fast, a mind too accustomed to taking others apart into traits.
Che set down his pen and rubbed his brow.
The mirror before the Transformation Technique reflected more than just a face.
It also reflected the kind of person he was becoming.