How old is Ui Ui in ‘Jujutsu Kaisen’?

Warning: Vague spoilers for Mei Mei and Ui Ui’s storyline during the Shibuya Incident Arc

Ui Ui and his older sister Mei Mei have a peculiar relationship in Jujutsu Kaisen, to put it nicely.

The Malaysia hotel room scene in season 2, episode 22, had most fans cringing hard for its incestuous undertones – not to mention apparent grooming. As a fan put it: “She’s essentially emotionally manipulating her siscon younger brother.” Even if it’s Gege Akutami’s attempt at once again hinting at Mei Mei’s twisted morality, it nevertheless feels wrong and weird.

Not to mention Ui Ui seems fairly young, a pre-teen at most. He might be more mature than most kids his age due to the circumstances he was brought up in and his role as a jujutsu sorcerer and his first-grade sister’s helpful anti-domain resource.

Has Ui Ui’s age been confirmed?

Mangaka Gege Akutami has never confirmed Ui Ui’s actual age or date of birth, as he has many other characters. All we know is that he’s young, much younger than his sister who is in her 30s. Most of us would agree he would ideally need a psychologist to unpack and deal with his problematic obsession with Mei Mei before his complex solidifies further with age.

On a Reddit thread that dubbed Ui Ui a “simp,” many commenters came to his defense calling him a “victim” instead, defending that he is a kid so he can’t know any better, or whether he’s being manipulated by his much more experienced, and undeniably shrewd sister. A fan also alluded to the implications of the spelling of the boy’s name:

We’ll likely never get a confirmation of Ui Ui’s actual age. It may be possible that Akutami wants to remark that this relationship is problematic regardless of how old the younger sibling is. But, as with many of the shocking choices the author makes, we may never know the true reasoning that’s behind it.