[Spoiler] Kento Nanami Dies? This is the theory "Jujutsu Kaisen"
Kento Nanami Died in the Shibuya incident. It was said that he could not withstand the attacks of the curse that continued to become and even involved the civilians in the attack of the cursed demon. Kento Nanami and several other jujutsu magicians help and eradicate the cursed demon that exists.
As we know, that the shibuya incident in this jujutsu kaisen anime is a very big incident and even Satoru Gojo was successfully sealed. With Gojo's seal, the cursed demons are increasingly confident to attack and kill civilians, including the killing of jujutsu magicians.
The Shibuya incident occurred on October 31st, Nanami received information that Gojo had been sealed and several assistant managers had been killed. Nanami rushed off to help Gojo while the others were asked to stay and continue guarding and assisting in the area. After that Nanami met with Maki and Naobito, They entered Shibuya Station and met with Dagon (Dagon is a cursed spirit).
Dagon manages to attack Nanami with his Domain attack. But Nanami managed to survive and helped Megumi to open a way out and rushed back. It doesn't stop there, After successfully defending from Dagon's attack, Nanami is attacked and dragged out by Jogo. It left him on the verge of death with terrible injuries.
There Nanami thought about her “Retirement Day” that she wanted to spend in a quiet country reading a book. He didn't regret it even though he was on the "Threat of Death". Around him there were many mutated humans and while Nanami just lay limp helplessly. In his dying state he still thinks of Megumi and her friends.
Well after that Nanami met Mahito. In a dying and helpless state, Nanami is killed by Mahito.