In the dynamic world of Jujutsu Kaisen, there have been a number of theories regarding Ryomen Sukuna's past. Considering the fact that the narrative never delved into the origins of The King of Curses, fans took it upon themselves to theorize and form a comprehensive backstory for him.
The hottest topic of discussion among the Jujutsu Kaisen fandom is probably the ongoing rivalry between Sukuna and the protagonist of the story, Yuji Itadori. Fans have come up with several theories about how the heated rivalry between the two characters might date back to the Heian Era, or how Yuji might even be a reincarnation of Sukuna's twin brother.
That said, the latest fan theory that is currently going viral on social media states that Yuji could possibly be Sukuna's doppelganger, which would apparently make them destined to fight each other for the right to live.
Jujutsu Kaisen: Fan theory suggests a deeper bond between Yuji Itadori and Ryomen Sukuna
Over the past few months, there certainly has been a surge in the number of theories regarding Ryomen Sukuna's relationship with Yuji Itadori in the Jujutsu Kaisen series. While it's known to every manga reader that Yuji was created by Kenjaku for the specific purpose of being the perfect vessel for Sukuna, some fans have theorized that the connection between the two might date back to ancient times.
A recent fan theory on X (formerly known as Twitter), suggested that Yuji might actually be Sukuna's doppelganger from the Heian Era. While some fans had initially thought that Yuji was a reincarnation of a sorcerer from the Heian Era, the fact that Sukuna claimed to have never seen a person like Yuji seemed to disprove this theory.
Doppelgangers have been a popular topic of discussion in pop culture for a long time, as the idea of having an unrelated look-alike seems both amusing as well as spooky. A person coming face to face with their doppelganger has for long been considered an omen of misfortune or bad luck. Furthermore, both in fiction and in traditions, doppelgangers are usually portrayed as the evil twin who represents the exact opposite, or rather, the dark side of a person.
That said, the theory claims that Yuji might just be the counterbalance that fate had specifically created for Sukuna, who's often considered a natural calamity. Sukuna has been portrayed in the series as a self-serving being, who always prioritizes his own interests before others.
He has been said to live by his own rules and standards, and views other people as mere playthings. He built a reputation for himself as the undisputed King of Curses by trampling over the lives of other people and destroying everyone and everything that gets in his way.
On the other hand, Yuji is the complete opposite of Sukuna. He has been shown to be one of the kindest characters in the Jujutsu Kaisen series, who goes out of his way to look out for others. By saving and protecting others, Yuji hopes to die in a meaningful way, where he is surrounded by his loved ones. While this approach often proves to be disadvantageous for him, he has never once faltered in his mission.
According to the theory, when Sukuna disrupted the balance of the universe by essentially becoming immortal, he inadvertently created a different version of himself. This version is Yuji, who represents all his opposite qualities and basically became the Yin to his Yang.
This theory is also backed by the fact that Yuji's appearance is somewhat similar to Sukuna's Heian Era form, which is something that was pointed out by fans a long time ago. If the entire concept of a doppelganger symbolizes the duality of human nature, then it would certainly make sense for Yuji to be the better part of Sukuna, whereas the latter would be the dark side of the former.
Often times in fiction, a person's entire existence is threatened by their doppelganger, as it is stated that only one version of them would be allowed to exist. As such, a battle of survival ensues between them, as both versions fight for their own existence.
This would mean that the fight between Sukuna and Yuji was fated to happen, as among the two, only one would be allowed to exist. Thereby, the clash between them was inevitable from the beginning, as the two characters are currently locked in a deadly battle for survival in the Jujutsu Kaisen manga.
So far, Yuji has proven to be a worthy rival for Sukuna. In the latest chapter of the manga, the latter was visibly impressed by his opponent's growth in the past few months. He even complimented Yuji's indomitable spirit, which was also notably one of the reasons behind Sukuna's hatred for him.
That said, Yuji learning the Reverse Cursed Technique was a crucial addition to his arsenal, which allowed him to go toe-to-toe against The King of Curses.
Final thoughts
The theory of Yuji being Sukuna's doppleganger is certainly one of the most interesting ones in recent memory.
Not only does it make the connection between the two bitter rivals even more important, but it also provides some form of hope that good might prevail over evil in the deadly clash between Yuji and Sukuna in the Jujutsu Kaisen manga.