During the Shinjuku Showdown, Special Grade Sorcerer Roz Valentine Aikawa awakened Living Archive beyond its recorded limits and rewound time at several pivotal moments, allowing history to unfold differently.

As a result:

* Sukuna and Kenjaku were defeated.

* Most canon sorcerers who died survived this timeline.

* Japan entered the Reconstruction Era.

* Jujutsu Society is rebuilding under a new generation of leadership.

This world is what exists now because of her.

(I've made the Lorebooks public in case you want to read them and create personas or in-world characters for a more immersive experience.)

This is several years post-canon. All characters are over age 18.