Jujutsu Kaisen has slowly been approaching its end. However, with that, fans could finally witness Kenjaku's plan come to fruition as his greatest creation might shatter Ryomen Sukuna's worldview.
As fans should know, Sukuna is a huge believer in the sole supremacy of sorcery. Thus, if a being that did not entirely rely on sorcery were to surpass him, it is bound to shatter his worldview.
Up until now, the Jujutsu Kaisen manga series hasn't really revealed Kenjaku's true goal. However, one Jujutsu Kaisen fan theory by @TopperGojo suggests that Kenjaku might have been attempting to create the perfect hybrid between Heavenly Restriction and Sorcery.
Disclaimer: This article contains spoilers from the Jujutsu Kaisen manga.
Jujutsu Kaisen theory suggests Kenjaku having created Yuji to shatter Sukuna's worldview
As revealed by the manga, Yuji Itadori is Kenjaku's son as he took over Kaori Itadori's body and gave birth to him. While the manga hasn't revealed much of the backstory behind Kaori, the process led to the birth of Yuji Itadori, who may be a hybrid between Heavenly Restriction and Sorcery.
This is evident from the fact that Yuji has great physical prowess on level or better than pre-fully realized Maki, one of the very few people to have Heavenly Restriction and zero cursed energy. Later, the protagonist even becomes comparable to fully realized Maki. This is because Yuta Okkotsu immediately compared Yuji to Maki even though he did not know about Yuji's history with Kenjaku.
As for sorcery, he was called a prodigy on par with Megumi Fushiguro. Initially, it seemed like Yuji took his sweet time to learn to use Cursed Energy, but soon enough, he was able to use Black Flash, and later also learned the Reverse Cursed Technique in just one month. His prowess was made especially evident when he defeated Mahito, a Special Grade Cursed Spirit, as a newbie.
In addition, the manga also hinted at Yuji having inherited Blood Manipulation from Kenjaku or some other Death Paintings' Cursed Technique after consuming them. Lastly, due to the time shared between Yuji and Sukuna within Yuji's body, Yuji became capable of seeing one's soul and directly attacking it. With such abilities, Yuji has become a capable fighter.
The reason why Sukuna's worldview would shatter is because he believes in Sorcery's supremacy. This was especially evident in Jujutsu Kaisen chapter 253 as Sukuna became so focused on defeating Maki, a person with Heavenly Restriction, that he used Black Flash on her. With that, it seemed like the fight was very personal for him as his ideals were on the line.
Even for Yuji, Sukuna would always call him "half-assed." This might have been a hint at Yuji not being a pure sorcerer but a hybrid between sorcery and Heavenly Restriction's physical prowess. Hence, if Yuji, a hybrid, were to get stronger than Sukuna, it would break the King of Curses' worldview.
Additionally, there might be another reason why Sukuna hates Yuji Itadori. Yuji was completely opposite from himself. While Sukuna thinks only for himself, Yuji lives for others. Thus, in every possible way, Yuji possibly surpassing Sukuna should shatter Sukuna's worldview.
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