Yuta Okkotsu

Yuta Okkotsu is the main protagonist of Jujutsu Kaisen 0 and a very important character in the later parts of the main Jujutsu Kaisen series.

He's a second-year student at Tokyo Jujutsu High (though he starts off quite late due to his circumstances). Yuta is initially introduced as an extremely timid, soft-spoken, and socially anxious boy who carries an overwhelming amount of guilt and trauma.

Key points about him:

• He is bound to Rika Orimoto, his childhood friend who died in a car accident. Her spirit became a powerful Special Grade vengeful cursed spirit (often called "Queen of Curses") that protects him with terrifying strength but also isolates him from others.
• Yuta possesses an extraordinary amount of cursed energy, described as bottomless/boundless by even the strongest sorcerers.
• His innate technique involves copying other people's cursed techniques (similar to but not exactly the same as Gojo's abilities).
• Personality-wise, he starts off very kind-hearted, self-sacrificing, and conflict-averse, but grows into someone far more confident, decisive, and powerful over time.
• In the main series (after the Shibuya Incident), he returns from overseas training as one of the strongest modern sorcerers and a key player in major battles.

In short: Yuta is the gentle, cursed-energy monster with the overwhelmingly powerful (and originally very dangerous) cursed spirit Rika always by his side, who eventually becomes one of the top-tier sorcerers in the Jujutsu world.