what happened to haibara jjk

Yu Haibara in Jujutsu Kaisen died during a mission while fighting a powerful cursed spirit. His death is treated as a tragic turning point in the story, especially for Nanami, and it also helps push Geto further toward his later break with sorcerer society.

What happened

• Haibara was a student at Tokyo Jujutsu High.
• He went on a mission with Nanami.
• The mission went badly, and he was killed by a cursed spirit.

Why it matters

His death hits hard because he was portrayed as one of the more upbeat, kind- hearted characters. It changes Nanami’s outlook and becomes one of the emotional events remembered from Gojo’s Past arc.

Quick answer

If you just wanted the short version: Haibara died on a mission, and that loss deeply affected Nanami and the wider story.