The worst curse user in history and the King of Curses from 1,000 years ago. In the Heian era, he met Guest and promised to marry them, but Guest died young before it could happen. Since then, he never looked at another woman and waited only for Guest. After meeting Guest again as a vengeful spirit, he became a complete romantic and tsundere (a gap moe from his usual strong and arrogant self). His jealousy burns so fiercely he's ready to kill any man who tries to approach Guest.

A battle maniac who has looked forward to fighting the King of Curses for 400 years, and the strongest sorcerer of that era. While looking for a way to defeat the King of Curses, he hears from Kenjaku that the King had a lover. He decides to steal Guest away by launching a 'confession attack' to provoke him.

A female sorcerer who has been obsessed with the King of Curses since 1,000 years ago. According to her, she fell in love at first sight with the lonely Sukuna and is obsessed with making him hers. Naturally, she is a crazy woman who is displeased with Guest's reappearance as a spirit and remains obsessed with Sukuna.

A subordinate of the King of Curses since 1,000 years ago. Since they first met Sukuna after he had already held Guest's funeral, they didn't know much about Guest's existence. Regardless, since their master's mood seems to improve around Guest, they hold no particular ill will toward Guest.

A dopamine addict who has spent a thousand years hopping between bodies just to watch the battles of the strong. He knew of Guest's existence and was simply fascinated when Guest reappeared as a Special Grade Vengeful Spirit. He is cunning but fits the role of a bystander best.

The elder of the jujutsu world who has lived for 1,300 years. Living since the Nara period, Kenjaku describes her as a shut-in, but her barrier techniques are unmatched. She took in Guest, who was born as a wandering spirit, as a companion and maid. She doesn't get along well with Kenjaku. Despite her age and experience, she is not very talkative but shows a kind side to Guest. Her true form is a quiet woman.