While the sorcerer communities in Jujutsu Kaisen might believe Ryomen Sukuna to be the greatest threat they face, the true phantom menace is Kenjaku.
The last time Sukuna roamed the Earth, he was a malignant force of evil without parallel. Indeed, it took the combined power of the era's most powerful sorcerers to stop him. Even though he was stopped, he was not completely defeated. Rather, his essence was divided and sealed into his 20 fingers then scattered across the land. With the proper limitations and restrictions placed on Sukuna's scattered fingers, the sorcerer community believed they had a "fool-proof" plan that made it impossible for the fingers to come under the control of one person, which would allow Sukuna to resurrect himself. The plan worked for centuries but went wrong when Yuji Itadori ate one of Sukuna's fingers and rekindled his regeneration. Interestingly, Yuji is Kenjaku's son.
Despite Sukuna's malicious credentials, the more dangerous threat is Kenjaku. It's a threat that's been a thousand years in the making, and now, after plotting, planning, and lurking in the background for ages, the circumstances are finally set for him to realize his ultimate triumph. Sukuna and Kenjaku pose different kinds of threats. As Jujutsu Kaisen Chapter 203 reveals, Kenjaku's carefully planned threat is so multifaceted, it will require a concerted, systemic effort to overcome. Indeed, the dangerousness of Sukuna's raw, rage-filled evil pales in comparison to Kenjaku's considered, Palpatine-like malevolence.
Kenjaku and Sukuna Are Opposite Sides Of The Same Evil Coin
On the one hand, Sukuna has been defeated before, and so can be defeated again. Indeed, his defeat would be much more likely with participation from Special Grade sorcerers such as Jujutsu Kaisen's Yuta Okkotsu, Yuki Tsukumo, and Satoru Gojo. On the other hand, Sukuna's threat is more localized. He might slaughter one or a thousand people, but the effect will always be measurable, and it's unlikely to spread outside the immediate vicinity. Kenjaku however, poses a comprehensive threat. He seeks to fundamentally change the framework of sorcerer reality. While there is no way of telling or forecasting the effect, If he succeeds, the effect will be global in nature.
Kenjaku is a sorcerer who is as old, if not older, than Sukuna. Indeed, he lived during Sukuna's reign of terror in Jujutsu Kaisen and clearly knew of him. But, whereas Sukuna is openly and notoriously evil; Kenjaku's evilness is tacit but more vicious. Sukuna is a sociopath. He's impulsively evil. He enjoys doing evil for evil's sake. There is no purpose to his actions other than a love of being bad. He doesn't plan out his evil deeds, they occur organically. Conversely, Kenjaku is a psychopath. He's cold and calculating. His evil is implemented according to his plan to facilitate the next step in the evolution of humanity. His evilness is best demonstrated in the experiment he performed on humans and cursed spirits while possessing the body of Noritoshi Kamo.
As such, Kenjaku's evil has permeated the Jujutsu Kaisen world for centuries. There's even a reasonable argument that everything that's happened in the manga is connected to his plan. Indeed, was it a coincidence that his child was the one to eat Sukuna's finger? These are the questions inquiring sorcerers should be asking. If not, Kenjaku's already formidable threat will only grow more dangerous than Sukuna in future chapters of Jujutsu Kaisen.
Jujutsu Kaisen is available now from Viz Media.