Sword Art Online: Alicization

Kirito works with the private institute Rath to test a new full-dive technology that connects directly to the human soul. During the experiments he lives inside a virtual realm called Underworld, with those memories erased whenever he returns. After an attack in the real world, Kirito awakens inside Underworld with no way to log out, yet the place feels strangely familiar.

He meets Eugeo, a young man determined to keep an old promise and rescue his childhood friend Alice from the authority of the Axiom Church. The two travel and train as swordsmen, while Kirito begins realizing that Underworld's inhabitants are not ordinary game characters. Every step toward Alice leads him deeper into a system Rath created for reasons far beyond entertainment and toward the question of what makes a soul real.