Come Be My Son

Kakashi Hatake was not an unreasonable child.

In fact, he thought far more deeply than most people imagined. In this chaotic era, he had already killed several bandits during missions and seen blood.

As for his situation, he had thought about it all night after returning yesterday and understood Aizen's intention to protect him.

It was just that adoptive father-son and master-disciple relationships in Konoha were not so simple.

Konoha had seen such arrangements before, but while they were called father and son, they were actually master and disciple. At their core, although Konoha's traditional education system was meant to lay foundations, the secret techniques and various forms of training of each clan often began in childhood.

It could be said that every Ninja trained through a master-disciple system was a living textbook of Konoha's secret techniques. Many techniques that could not be written down and could only be passed on through feeling continued in Konoha this way.

Thus, beyond the academy's education, orphans were often taken in as Adopted Sons or passed down through master-disciple relationships, preserving those techniques and secret arts in Konoha through another method.

But Sosuke Aizen was neither a powerful Ninja nor the holder of secret techniques, and he was not that old either. Why did he want to be an adoptive father?

Being an older brother or uncle would have been fine, but wasn't being an adoptive father a bit much?

"Are you considering the matter of my strength, Kakashi-kun?"

Seeing Kakashi Hatake's surprise, Aizen smiled and spoke gently.

"There is a decisive gap even between Chunin and Genin, Kakashi-kun. You may attack without concern. After all, I know that Sakumo-kun's words have made you wary of me. In that case, shouldn't a father and son have a more open discussion?"

"...I understand."

Looking at the gentle-faced Aizen, Kakashi nodded.

The next instant, Kakashi Hatake drew a Kunai from his clothes and thrust it at Aizen's shoulder.

Even an ordinary Jonin would never have been able to react in time under such circumstances.

The shoulder will do. After all, he's doing this for my sake...

Kakashi thought as he shifted the Kunai that had originally targeted Aizen's neck, redirecting it toward his shoulder.

Yet Kakashi did not feel the sensation of piercing flesh. He only heard a harsh sound, as though metal had struck metal.

Clang!

Six-year-old Kakashi Hatake's eyes widened as he looked at Sosuke Aizen, who had stopped his Kunai with his fingertip as though it required no effort at all.

"This is the truth, Kakashi-kun."

Aizen gave a gentle smile at Kakashi's shocked face.

Pale Blue Chakra, nearly sharp-edged in form, flowed and intertwined across Sosuke Aizen's fingers.

With his heartbeat and breathing, azure ripples flickered along fixed pathways, making it appear as though his fingers had been Solidified into a single whole.

"Then, as my Adopted Son, this will be the first gift I give you."

One finger was curled around Kakashi's Kunai, while Aizen used his other hand to push up his glasses. Looking at the horrified Kakashi before him, he smiled and said,

"A defensive secret technique. This is what I wish to give you. I never wanted children like you to go to the battlefield. The First Hokage thought the same. But in this world, without strength, one can only be butchered by others."

"Though I only came into contact with the battlefield briefly, scenes of people killing people still made me feel sorrow. I do not possess the powerful healing abilities of a Medical Ninja, nor do I have any particularly exquisite control over Chakra. But humans are creatures skilled at thought."

"After injecting or applying a series of Chakra-reactive solutions to the body's surface, once Chakra begins to circulate, a thin but powerful layer of defense automatically adheres to the body. Combined with certain seals and trigger-type talismans applied and added beneath the epidermis, this technique can be completed. Its Results are as you see now."

"Based on its state and operating principle, I gave it a rather fitting name."

"Blut Vene."

The sharp Kunai in Kakashi's hand could not even pierce the outermost layer of skin. Before Blut Vene's true defensive module, it was like stabbing directly into a steel plate, producing a harsh scraping sound.

Facing Kakashi Hatake, Konoha's foremost Genius who possessed nearly Chunin-level strength, Sosuke Aizen used one hand's index finger to block his attack. Still with strength to spare, he sat upright in the center of the Writing Room, smiling at the gritting young boy.

No matter how the boy exerted himself, whether cutting or pressing forward with all his strength, the blue-glowing finger stood between them like a mountain. With only a slight bend, it locked the entire Kunai in his palm.

"Because it requires control over the blood and Chakra within the body, the current Results of its development mean it can at least block ordinary slashes and Ninjutsu from ordinary Genin and even Chunin."

Seeing Kakashi Hatake, whose mask did not hide his wide, round eyes and whose exertion had clearly reached its limit, Aizen gave a soft laugh.

"You cannot even damage a single strand of my hair, Kakashi-kun."

"This is also my advice to you. Do not play by your enemy's rules. You will certainly come to taste regret."

"The tools and conditions required to use Blut Vene are too demanding, so it can only be concealed with a Haori. That is why, with the Third Hokage's special approval, I can move freely through Konoha wearing a Haori and without a forehead protector."

"When someone possesses privileges others do not have, do not become indignant. Instead, begin considering whether he possesses some other unique quality. Simple jealousy will blind your vision and cause flaws and errors in your judgment."

"Tch!"

He was clearly just a Chunin, a bottom-ranked failure Father had spoken of!

Looking at Aizen, Kakashi openly displayed his disgust. His somewhat small figure instantly transformed into a piece of Calligraphy and Painting bearing the words "No Retreat."

Smoke instantly spread through the entire Writing Room. Kakashi Hatake silently used the Substitution Technique to move behind Aizen, then hurled several Kunai at the unguarded Haori.

"...The Substitution Technique?"

Aizen's voice was low and magnetic as he looked at the writing in his hand.

"An excellent judgment. Since you could not break through from the front, using continuous attacks from behind was a good idea. But, Kakashi-kun, this is useless."

Clang.

Seeing the Kunai embedded in Aizen's back, which had only torn part of his Haori without advancing an inch further, the shock in Kakashi Hatake's eyes grew stronger.

What the hell was this thing?

He had never even heard of a technique capable of resisting slashing, chopping, and stabbing damage like this.

"Do you understand now, Kakashi-kun? This is the first gift I wish to give you. An unranked special operational technique: Blut Vene."

From his Eyes to his hair, from his fingertips to the soles of his feet, there was not a single part of his body untouched by Blut Vene's radiance.

The several Kunai, their force spent, slid down from his back and fell directly onto the wooden floor with dull impacts.

Sosuke Aizen sat properly on the floor, turning to look at Kakashi Hatake standing on the beam, who was already somewhat at a loss. He smiled and pushed up his glasses.

"This technique is a life-saving skill I hope to teach every Konoha Genin. But unfortunately, when Blut Vene is active, it greatly interferes with the circulation and release of Chakra. Therefore, I recommend using swordsmanship and close combat to determine victory."

"I told you, Kakashi-kun. I care deeply about your life. You are the son of Konoha's White Fang, Sakumo-kun. I will not judge his choice, but I hope you can accept this gift."

"In order to achieve the Will of Fire, I can personally decide to give this secret technique to you."

"Besides, I would feel very sorry leaving the child of a familiar comrade alone in this world. Please consider it, Kakashi-kun. I respect your choice. Even if you do not wish to become my Adopted Son, please keep this secret technique."

"..."

Like moonlight, cool and distant, yet carrying a mysterious elegance.

Sosuke Aizen took a scroll from his Haori's long sleeve and placed it on the wooden desk, looking toward Kakashi Hatake on the beam with a complicated expression.

When a person's actions were sincere, their expression was sincere, and they were truly willing to take out their own things to help others, should he still heed his family member's words and treat that person as an enemy?

Looking at Sosuke Aizen's warm, approachable smile, then at the secret technique scroll he had placed on the desk, Kakashi Hatake felt his resolve constantly wavering.

He was only six years old. Apart from his father, only Sosuke Aizen truly respected his will and offered him encouragement.

Just then, as though to keep them from feeling awkward, a Ninja dressed entirely in pitch black suddenly appeared outside the Writing Room.

"Chunin Aizen, the Third Hokage invites you to attend a meeting."

"Ah, I will go at once. Thank you for delivering the summons."

Seeing the ANBU who had instantly appeared before the Writing Room and knelt on one knee, Sosuke Aizen nodded gently. He set aside the "No Retreat" in his hand, stood, and looked at Kakashi on the beam.

"Please consider it carefully, Kakashi-kun. I think very highly of you, so do not disappoint me. My talent is limited, and I have little idea how to further develop Blut Vene. Only a Blut Arterie that reverses the Blut Vene state remains theoretical. You may be able to do better. Well then, I am leaving. Make yourself at home."

"..."

Facing the scroll Aizen had left on the desk, Kakashi only felt the emotions in his heart becoming increasingly strange.

Sosuke Aizen... was he really an ordinary Chunin?

Looking at the large character for "Genius" written on the desk, recalling how Aizen had caught his Kunai with one hand, along with the Third Hokage's invitation, a bizarre thought flashed through Kakashi's mind.

The Third Hokage could not be wrong, and the ANBU and the major Ninja could not possibly allow a holder of untrusted secret techniques to move about so freely.

Not to mention, being personally invited by the ANBU to attend a meeting was an immense honor.

And everyone in the village liked him. Even members of the Uchiha Clan treated him with courtesy.

Most people said he was a genuinely good person, and his actions supported that. Only Father had said otherwise.

But Father had committed suicide.

Kakashi gradually reached a deeply rebellious conclusion.

Perhaps... Father was really the one who was wrong???

The boy stood on the beam, sinking into the greatest confusion of his life.