Jujutsu Kaisen: Why can Yuji hurt Mahito? Explained
Jujutsu Kaisen episode 20 recently came out, and there were a lot of great moments, such as Aoi Todo's entrance, Yuji and him fighting Mahito, the latter using the Black Flash technique, and a lot more. And perhaps the most surprising element was the fact that Yuji could do permanent damage to Mahito, especially considering the latter's nature and how he can regenerate with ease.
Throughout the entirety of Jujutsu Kaisen, Mahito has been mostly unable to receive damage, and that is due to the very nature of his character, being the Cursed that embodies human hatred. However, even the character himself has mentioned that Yuji Itadori is "his natural enemy," and this is because of something that was explained the first time they fought one another.
Disclaimer: This article contains spoilers for the Jujutsu Kaisen series.
Explaining why Yuji can hurt Mahito in Jujutsu Kaisen
It's been established since Mahito's introduction in Jujutsu Kaisen, when he first fought Nanami Kento, that he couldn't be hurt by people who didn't have an understanding of the soul. According to Mahito, the soul exists before the body, and the former shapes the latter, so in order for him to be hurt, the other person needs to have an understanding of his own soul.
Because Yuji Itadori is the vessel of Ryomen Sukuna and has to keep him at bay at all times within him, he has learned to understand his own soul, which, in return, has allowed him to hurt Mahito. This is why the Curse himself says that Itadori is "his natural enemy". Because he is perfectly suited to hurt during their confrontations.
This could also explain why Mahito wanted to make Yuji suffer so much: it is a way to torture his natural enemy and also to mentally weaken him in order to kill him. It is also a smart thematic structure by author Gege Akutami, as both characters are direct opposites of one another in many different ways throughout the entirety of the Jujutsu Kaisen series.
The value of the rivalry between Yuji and Mahito
The rivalry between Mahito and Yuji is probably one of the most appealing aspects of the Jujutsu Kaisen series because Gege Akutami built it for a couple of arcs. The moment where they have their final confrontation in Shibuya has been building up since Yuji met Junpei Yoshino a couple of arcs ago, which is something that makes the battle all the more engaging to the reader or viewer.
Mahito is a profoundly selfish and evil character, doing things for his own pleasure and with no regard for anyone else, which is a direct contrast to Yuji's good-hearted and selfless nature, making their rivalry all the more entertaining and fleshed out. There is also the fact that Mahito killed Junpei, Nanami, and Nobara and did it right in front of Yuji, giving the latter even more reasons to take him down.
A lot of fans have argued that Yuji's character peaked during the Shibuya Incident arc, and if that was the case, then Mahito's influence was very useful because they contrast extremely well and have a very entertaining dynamic.
Yuji can kill Mahito because the latter can only be hurt by those who have a certain understanding of their own soul, and the former does this because of his experience as Sukuna's vessel. This was a concept that was explained in the earlier portions of the Jujutsu Kaisen series.