"Uncle Itachi, do you have a way to save him....or maybe my father could? He is also a Shinigami, right?" Karin quickly listed all the possibilities she could think of.
"Only you can save Ichigo now."
"I? I don't know how to use any powers."
"I can teach you."
"But, won't that be too late?" Karin asked quickly.
"I know a way to pause time for us....While time is paused, I can awaken your Quincy bloodline and teach you all Quincy techniques."
"Then, Uncle Itachi, please." Hearing the solution, Karin got up and bowed deeply in request.
"But I am warning you...this process might kill you, and even if it doesn't, it won't be easy, as it will take years of hard work. Are you really sure about your decision?"
"Yes."
Hearing Karin's answer, Itachi nodded in satisfaction. As for why he was doing all this?
Well, all this began with his unexpected discovery of something in the World of the Living last month. He discovered a Leg....with immense spiritual pressure in the deep sea. After repeated investigations and experiments, he concluded that this was the Soul King's right leg, which wasn't shown in canon.
Then, a thought came to him....What if he could absorb the power of this leg or steal it's power so that he can gain a power like Stagnation or Miracle.
Then another thought rose, what if he stole all the power of the Soul King instead of Yhwach? That would definitely increase his strength and hax.
Thus, for the past month, Itachi searched for all the parts of the Soul King scattered throughout the World of the Living and gave the three great scientists the task of finding a way for him to absorb the Soul King perfectly, as he didn't have Yhwach's connection to the Soul King or The Almighty to devour its powers.
Though, ultimately they weren't successful. So Itachi thought of his next plan....which was to become a strong independent wom— ahem, scientist. The main barrier blocking the three great scientists was that they couldn't properly interact with the soul, spiritual energy, or Reishi of the Bleach verse with their physical body. Even the science here worked with Reishi, let alone the Soul King...so only he, who was a Quincy, could do this.
But even if he started learning now, it would take years to learn everything and then start solving the problems, so he chose to use his first cheat code....Life-Death Arena....but going there alone was too boring, nor did he bring Izumi or some companion who wasn't a creepy scientist or an old man.
So he thought of playing a game....with real characters. And Kurosaki Karin, the sister of Ichigo who had wasted potential in Bleach, was the best character, and it could be an interesting pastime for him.
As for why make an eleven-year-old girl waste the prime years of her life on some boring practice if Ichigo would still be saved without her help? Well, he was making a strong independent woman.
"Good...then LIFE-DEATH ARENA."
With Itachi's command, both Itachi and Karin disappeared as they appeared on an endless ocean.
SPLASH SPLASH SPLASH SPLASH
"Help....help...Uncle Itachi, help...." Just then, Karin's cries broke Itachi's state of admiring the beautiful world.
SWOOSH
"Sorry, I forgot you can't fly or stand on water." Looking at the drenched Karin, Itachi waved a gust of hot air toward her, drying her clothes while apologizing.
"Uncle Itachi, where is this?" Looking at Itachi's sincere apology, Karin let the matter go as she looked at the water on all sides in wonder.
"This is a special dimension....However much time passes in here, in the outside world less than a second will pass."
"Woow, that's amazing, but....where will we live and train?" Looking at the lack of any island, Karin asked worriedly.
"Well, that's nothing to worry about....this is my portable city....CITY OF ASTERHAVEN." With Itachi's words, both Itachi and Karin flew higher and higher as, suddenly, a huge city more than hundred square kilometers in size appeared below them.
"Is this the power of a Quincy?" Karin, after being speechless for a while, asked Itachi in shock.
"That's not a Quincy's power but mine....Anyway, we are going to live in this city for a while. Inside there are dozens of shopping malls, gaming cafés, auditoriums, amphitheaters, and whatnot...so you do not have to worry about living the miserable life you have in your mind."
"That's amazing!!!"
For a moment, Karin forgot about everything as she looked at the city. This was the same city he had built in the OPM verse, and it was at least decades more modern than the current Bleach timeline, attracting Karin's attention with its huge buildings and many other things.
"You have today as a vacation....You can roam the city as you wish and use anything you like.....There is an Android civilization living below, so be polite with them. As for your residence, you can live in the central mansion where I live or anywhere you like."
With that, Itachi teleported Karin to the ground, watching her roam through the city of the future.
As for the Android civilization...it's just robots controlled by a super AI, acting as the managers of the city and also making the city less lonely and more crowded.
He wanted to play the game, and Karin was the character, so of course he couldn't let her suffer. His current goal was to level Karin up to at least Captain level while starting his own scientist arc.
For this, he had made many preparations, such as storing all the books and knowledge of the Ninja World and OPM World in Daikokuten, and he also stol— ahem, borrowed Urahara's entire lab into Daikokuten for this occasion.
He also had the assistance of the OPM and Ninja World's most advanced AI....So all hail the Soul King!
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Next Day
"Good morning, Uncle Itachi." Karin gave Itachi a polite smile and greeted him seriously.
"Hmm...from now on you will call me Sensei or Itachi-sensei."
"Yes, Itachi-sensei."
"Good...then we will start your training today....Drink this!"
Itachi, seeing the attentive Karin, nodded as he handed her a transparent glass container filled with bluish liquid.
"What is this?" Karin opened the bottle curiously as she gulped the entire 30 ml down in one sip.
"This is the Optimized Biceps Brachii King Serum....Hey, the effects have started."
Itachi stopped midway as Karin started to grow bigger and bigger until, within a few seconds, a two-hundred-and-fifty-meter-tall giant resembling the Female Titan from AOT, except with long black hair, appeared before him.
"Itachi-sensei....Is this the effect of that liquid?....I...I feel full of strength, as if I could punch this city to pieces with one punch...."
Karin's voice boomed throughout the city as she excitedly punched the sky, causing a sonic boom.
"Today's lesson is fighting....Karin, try your best to hurt me."
"But, won't that destroy the city?" Looking at the city, Karin was still reluctant to attack.
"Don't worry about it, I can control time....so be free to use everything."
"Okay....then be careful, Itachi-sensei!"
With that, Karin took a step back and kicked toward Itachi as if kicking a soccer ball.
"Karin, from now on I will only use my Quincy powers....Although I won't awaken the power within you before you master this form, you can still try to learn or get familiar with it.
This is the movement technique called Hirenkyaku."
With that, Itachi formed a small Reishi platform beneath his feet and glided through the air at high speed as he dodged Karin's kick.
Although Itachi dodged it, the buildings and structures behind him weren't as lucky, as a row of buildings collapsed, dividing the city in two.
"Should we stop?" Karin stopped after seeing the destruction she had caused and looked at Itachi.
Time Reversal
Itachi didn't say anything as, with a snap of his fingers, all the destruction Karin had caused reversed within a second, making Karin almost believe she had hallucinated.
"Continue until you are tired...."
So for the next three hours, Karin truly let loose as she tried everything she remembered from watching movies and those kickboxing shows, destroying the entire city into rubble.
"Sensei...you are too strong." Looking at the city, which had been completely destroyed a few seconds ago and was now fully restored, Karin said in admiration.
"Okay...now can you change your size?"
"Ahh, no. What should I do?"
"I will help you now, and this is your first stage of training.....Change your size independently based on the situation and compress your power."
"Yes."
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