According to the detailed content, Yuji’s father, Jin Itadori, is the reincarnation of Sukuna’s twin brother, making Yuji the grandson of Sukuna.
When Sukuna was still in the womb, he had already made arrangements to reincarnate his twin brother to avoid dying. This explains the unusual appearance of the hound. Gege drew inspiration from ancient Japanese mythology for “Ryomen Sukuna,” a being with two faces and four arms, each set facing front and back.
The term “Ryomen” also means two faces. Even in Japanese folklore, Sukuna is often depicted as a pair of intertwined twins.
Jujutsu Kaisen Chapter 257 begins with a brief conversation when Uraume brings Sukuna back to Yuji. Uraume notices a certain mutual relationship between Yuji and Sukuna.
Sukuna explicitly states that Jin Itadori is the reincarnation of his twin brother. Kenjaku gave birth to Yuji after he seized Kaori Itadori for a particular reincarnation plan, even embedding some of Sukuna’s cursed energy within Yuji’s fingers.
Although many theories suggest that Sukuna and Yuji are identical twins, the reality is much more complex than what the audience perceives. On the other hand, the theory regarding Sukuna harming his own twin brother, which originates from a legendary folklore in Japan, turns out to be a misconception.
However, the narrative focus is that Gege chose this particular battle to reveal Yuji’s true origins, aiming to interpret how both can utilize the same technique, regardless of whether it is a healing object or any other tool. Sukuna and Yuji share the same bloodline, and both can wield the technique “Mizushi.”
Despite this, there are distinct differences in how the two utilize Mizushi, considering their backgrounds and how they approach its use.
It is unclear at which point in Jujutsu Kaisen that Sukuna becomes aware of the mutual relationship with Yuji. Ultimately, when the King of Curses first attempts to seize Yuji, he is quite surprised to find someone capable of suppressing him. The King of Curses initially reincarnated but even wondered who Itadori was at that moment.
