Yukiin was unaccustomed to allowing the free flow of his mental state from one mood to another, the current of life's whims carrying him, but he was learning piece by piece that it was not something he could freely permit as the opposite extreme of his previous state of being; it was a delicate balance like an elephant walking a tightrope...but nobody paid for tickets, nobody knows its an elephant...a terrible analogy in hindsight. He was considering this because the first impulse in his head that was not a rational thought was to smash the leech across the skull for such a gross misunderstanding of her station and her position in the village. It was like Osuteno said, Kumogakure produced too many shinobi who didn't understand their place and either were useless or were bullies. Neither was helpful to the development of new soldiers, it only made them weaker...though he suspected a similar process had made Kei what she already was, someone had intervened in her development and made her less than what she was supposed to be. He wouldn't permit that cycle to continue, not under his supervision.
The younger boy's question was also an odd one, Yukiin wasn't from this land either and yet he'd adjusted adequately and found himself in a good position, growing and developing into a fine shinobi. It was a strange thing and he was uncertain what exactly he meant, was he unaccustomed to the level of strength even weak shinobi possessed? They were weapons of war after all, deploying even a Genin was like wheeling a canon up to your enemy's gates and lighting it. This was why they had to be skilled in stealth and espionage in addition to brute force because everyone knew what they were capable of and thus even the suspicion of their involvement in foreign affairs made the enemy change tactics. This also was something he'd gleaned from his physician, that the young were not being trained to understand their position in the world and what they were because of the aforementioned incompetence or lack of self-control.
Living examples of theoretical concepts that the puppeteer didn't like to look at...lovely.
"It isn't our place to determine the weak or the strong." Yukiin responded curtly, with plenty more to say on the topic but deciding that it was best left communicated without words. She was perceptive, if anything, and he doubted she would miss his distaste though whether or not she processed it smoothly was another matter. Her behavior and outlook were childish after all, in the very literal sense, and that did make predicting her behavior a less than simple affair as she swayed from mood to mood. He supposed that was what could happen to him if he allowed himself to follow every impulse.
But he passed that mood of his by reeling it back by the leash, the furrowing of his brows yielding to a more pleasant, though still distant, response to the boy's confusion.
"Shinobi, yes. Though she is correct, you are weak...but thats what you're here to fix, whether or not you chose that path. You'll be molded into a more...suitable vessel for the inhuman abilities you will be asked to develop, cultivate, and utilize in service of Kumogakure. Its just chakra, something that Genin and Genin equivalents are capable of using reflexively and innately, its the same as breathing. She hurt you because, to her, you're a paper mache doll without the defense of chakra, this is why medical shinobi like myself exist - to minimize causalities caused to the village and to maximize casualties caused to the opposition; though the latter is admittedly my own addition to the branch philosophy."
The snowy haired Haku snapped one of his porcelein hands and extracted a large, ornate, spear from the air with the delicate pull of removing cobwebs rather than the intricate force of chakra, air, and water that was going on beneath the surface. The pillar of reinforced ice slid easily into his hands with the breath of white mist that had birthed it dispersing as the creator's fingers slid across its grip. He pointed the edge upwards, handing off the blunted end to the student in front of him...though admittedly it was an awkward position since he wasn't much taller than he was, something Yukiin choose to pass out of his mind.
"Chakra, its something like magic and something you inherited as an Aburame whether you understand that yet or not but I'll try to explain the brief version using what you're holding. If you would, gently so as to not undue my work, tap the tip of the spear with your finger and confirm that it draws blood as it should. The ice that my designation, Haku, produces is stronger than steel and a better cut so to illustrate for you best the reason you sustained the injuries that you did?"
He snapped his fingers again, producing another spear, with the same motion reaching forth and driving the spear in a practiced thrust into the flesh of one of the nearby trees until it slid through to the other side of the trunk, quietly and with little fanfare. It was like sliding through butter for Yukiin and he took his hand off the weapon, allowing it to dissolve into powder and disperse.
"Push your spear through your favorite tree and you'll find similar results. A shinobi's whole body is a weapon and these little ice pokers are an example of that, the reason you were hurt so badly is the same reason a tree trunk can't stop an ice spear - to a shinobi, anything that can't use chakra is defenseless...though don't misunderstand, a stray crossbow bolt to the face is still a problem because most of us are still human but its like being a different type of human. I won't bore you with the details of how this all works, in my experience students tend to prefer hands on work."