What Kurama Yakumo saw was naturally not the real Ten-Tails. It could not even be considered a projection.
It was merely something Sasuke had created by imitating Ido, the resentment-born inner demon of Kurama Yakumo from the original timeline, in order to awaken his Mangekyō Sharingan.
Sasuke had built it around Freud's theory of the id from his previous life, combining it with this world's psychology books and Uchiha genjutsu hypnosis.
The id was the earliest and most primitive part of a creature's personality, a repository of biological impulses and desires. Unbound by morality or notions of right and wrong, it pursued the greatest possible satisfaction of its own desires.
It consisted of all the psychological deposits embedded within a living being from birth: irrational, unconscious vitality, inner drives, instincts, impulses, desires, and other mental faculties that had been repressed and cast aside.
In the West, the id was called original sin or the devil in one's heart. In Eastern culture, it was known as an inner demon and the inherent evil of human nature.
Sasuke's practice of the Yoga Meditation Technique emphasized clearing away distracting thoughts, achieving a mind as still as water, and immersing himself in a tranquil, ethereal inner world.
Yet in order to nurture his inner demon, after completing the Yoga Meditation Technique each day, Sasuke did the opposite. He endlessly magnified the distractions, desires, and instincts in his heart, even using self-hypnosis for better results.
Then, through the Sharingan's genjutsu, he gathered and sealed away the accumulated negative emotions. This had taken more than a year.
A few days ago, the primitive biological impulses and distracting desires Sasuke had continuously accumulated had finally taken form within his heart as a monster resembling the shadow of the Ten-Tails!
A monster inherited from deep within the Uchiha clan's genes!
"Sasuke, do you know? If you do this, the negative emotions in your inner world will no longer be mere negative emotions. They will completely become a second personality—a personality of dark desire. It may even turn against you and take over your body!"
Kurama Yakumo urged him anxiously. She truly did not want this young man to undergo such a drastic change in personality and become a monster filled with resentment, vengeance, and desire.
Besides Sealing the Five Senses and the Demonic Illusion Realm, Kurama Yakumo's Kekkei Genkai also possessed the ability to turn illusion into reality and falsehood into truth. In the original timeline, she had painted a bolt of lightning onto the Hokage Building in a picture frame, and the real Hokage Building had been struck by lightning as well.
Even Kurenai Yuhi's Fuinjutsu had been utterly ineffective against the negative emotions in her heart. Her resentment and darkness had continued growing until they became the dark personality within her heart—Ido.
In the end, Ido, that illusory entity formed from negative emotions, had even separated from Kurama Yakumo's body and become a real monster capable of descending into reality.
"Let us seal him away instead. Wasn't that what you asked me to do before?"
What Sasuke had asked of her before was to seal away the darkness in his heart.
Kurama Yakumo had been somewhat hesitant about this. In her view, everyone had a hidden dark side, and blindly suppressing or destroying it would only backfire.
Moreover, a person completely devoid of a dark side could no longer be considered a whole person.
Only because Sasuke had been so resolute did Kurama Yakumo agree. Yet she had never expected the darkness in his heart to be so terrifying, much less that Sasuke wanted to make that dark side real and release it.
"It does need to be sealed, but not now."
Sasuke shook his head and replied calmly, "I already understand your concerns. Believe me, I will not be devoured by it. Its power will instead become mine to use."
Although Kurama Yakumo possessed the ability to transform illusion into reality, it was naturally impossible for her to turn the shadow of the Ten-Tails in his inner world into the real Ten-Tails based on nothing but a tiny fragment buried deep in his genes. Not even a hundred or a thousand Kurama Yakumos could accomplish that.
All Sasuke wanted was to turn the shadow of the Ten-Tails into his dark personality. The negative emotions in his heart were ultimately illusory, born from his training and hypnosis.
Like a reflection of flowers in a mirror or the moon in water, they would shatter at a touch. Only with Kurama Yakumo's help could he turn them from illusion into reality, transforming them into the true dark side of his heart—his second personality.
Into the dark Ido that belonged to Sasuke's heart!
"But..."
"Believe me, Yakumo." Sasuke's expression became much more serious this time.
"I still bear the blood-deep hatred of the Uchiha clan, and I carry the mission of restoring the Uchiha clan. Before I achieve that goal, I will never allow myself to die, nor will I allow myself to be consumed by my own darkness!"
To demonstrate his resolve, Sasuke invoked the Uchiha clan.
Hearing this, Kurama Yakumo fell silent for a long while. She glanced at the vaguely visible monster, then at Sasuke's resolute expression, and sighed inwardly.
"Alright."
"Sasuke, then I'll begin."
"Mm. Thank you, Yakumo."
Kurama Yakumo looked at the twisted, frenzied monster's shadow, worry flashing through her eyes as she swiftly formed several hand seals.
"Genjutsu: True Reality!"
As Kurama Yakumo unleashed her technique, surging torrents of air instantly rose throughout Sasuke's inner world and spread without end. Before long, it was as though heaven and earth were collapsing—the blood moon scattered, and the ground crumbled.
Countless negative emotions from biological genes and his inner world—twisted madness, bloodthirsty savagery, vicious malice, impulses, desires, and more—were continuously swallowed by the shadow of the Ten-Tails.
The shadow of the Ten-Tails repeatedly let out roars of resentment, gradually condensing into a clear, incomparably massive physical Ten-Tails that seemed capable of devouring the heavens.
How terrifying!
The instant Kurama Yakumo saw the materialized monster, she felt pain, distortion, desire, fear, resentment, and countless other emotions crash into her mind like raging waves. Her face instantly turned pale, and her head buzzed into a muddled haze.
What frightened her even more was that the strongest and most concentrated emotions emanating from this monster were—devouring and plundering!
It was as if this monster had been born solely to devour and plunder!
Even a considerable amount of the Yin Release chakra Kurama Yakumo had cast upon the monster was devoured and absorbed.
Without changing expression, Sasuke stepped in front of Kurama Yakumo, blocking the pressure and intimidation radiating from the Ten-Tails in his inner world. Yakumo was finally able to breathe a sigh of relief.
The moment the Ten-Tails monster took shape, it opened a scarlet, ferocious Sharingan and fixed its gaze on Sasuke.
Sasuke remained calm as he met its gaze without yielding. Man and beast simply stared at each other in silence.
Suddenly, the Ten-Tails monster's body began to tremble violently and collapse. Chunks resembling flesh yet also wood continuously broke apart, and its mountain-sized body shrank more and more amid the disintegration.
No one knew how long passed before the Ten-Tails monster's body completely crumbled away, revealing what lay within it.
Before you continue