When Naoya is defeated by Maki, it will be the moment she is considered to have strength equal to Toji in Jujutsu Kaisen.
Jujutsu Kaisen Chapter 198, Titled 'Sakurajima Colony Part 8,' Chronicles Naoya's Unusual Use of Domain Expansion. While his lower body retains the kettle-like form from before, his upper body regains its original human shape, enabling him to utilize hand seals to unleash his domain.
Naoya's domain, the Time Cell Moon Palace, manifests with a colossal eye at its center, later explained as a trigger for a formidable technique within the boundary. Daidou and Miyo find themselves trapped inside the domain, and their necks are affixed with something resembling film strips from a camera. Both perceive the embeds but dismiss them as a mistake, feeling no sense of disorientation.
Deciding it's the opportune moment to strike, Daidou and Miyo simultaneously charge towards Naoya. However, as soon as they initiate their movements, wounds appear on their bodies, and they start bleeding from their eyes and noses. Jujutsu Kaisen Chapter 198 then elucidates on the workings of Naoya's domain, confirming that it relies on the Cursed Technique of Projection.
Naoya then explains that anyone he touches must mimic his movements exactly or be frozen for a second, and his domain amplifies the effect to a mobile level. Once affected by the Cursed Technique within his range, any movement will destabilize the cellular cohesion of their bodies, causing severe internal organ damage.
Jujutsu Kaisen Chapter 198 reveals that Miyo cannot withstand the impact of her cellular structure, collapsing first. She falls to the ground and acknowledges that it is indeed a formidable domain, a fact to which Naoya arrogantly agrees. He then shifts his focus to Maki, someone he still cannot perceive.
Earlier in the battle against Noritoshi, Naoya remarked that Maki shares a similarity with Toji in the aspect of concealing her presence, so he initially did not perceive her absence. However, he realizes that within his domain, at the very least, he should know where Maki is, even if he can't sense her due to her cursed energy deficiency.
Daidou seizes that moment to attack, and Naoya swiftly severs his arm, cautioning him against starting a futile battle while he's contemplating. Daidou simply smiles as both hands emerge from the shadows to grasp a sword and stab Naoya from behind.
Jujutsu Kaisen Chapter 198 also explains that, much like Toji, Maki lacks cursed energy. This leads to jujutsu techniques treating her similarly to how they interact with inanimate objects like buildings. The chapter further states that without her consent, no barrier can prevent her and references Megumi's domain from Domain Expansion #1 in Tokyo, stating that only an external barrier like that can trap her inside a domain.
Chapter 198 then shifts to a coastline where Maki and Mai hold hands. Mai tells her sister that she let Daidou "deal with" her to see what the katana is capable of, confirming that the katana has permeated Mai's spirit.
The chapter details that the katana Mai created is a replica of Toji's cursed tool worth 500 million yen, a soul-severing blade. The katana can bypass the hardness of external materials and directly cut someone's soul. However, using the katana at its maximum potential is impossible unless the user's senses are sharpened enough to even perceive a soul within inorganic matter.
Although Maki thrusts the katana straight into Naoya's chest, it doesn't immediately kill him. Naoya turns back, deriding and mocking her, stating that she will die for being unable to kill him in a single strike.
Naoya confidently asserts that Maki can no longer move as she is within his domain, transforming back into the bizarre caterpillar-like form due to the damage to his soul. However, the assured attack technique of the domain has no effect on Maki as she lacks cursed energy. She slashes through him, killing him and dismantling his domain.
Jujutsu Kaisen Chapter 198 concludes with Daidou and Miyo noting that they managed to escape in the nick of time, while Maki steps out with her katana and the remnants of the shattered domain. The chapter content mentions that a battle on par with Toji has finally resurfaced.