Kirito

Lore & Background

In the real world, Kazuto discovers that 300 SAO players remain trapped in their NerveGear, though Asuna is not among them as her consciousness is held in ALO by Sugou. He goes to the hospital to see Asuna and meets Shouzou Yuuki, Asuna's father, who is pressured by an associate of his, Nobuyuki Sugou, regarding a decision—later revealed to be Sugou's marriage with Asuna, angering Kazuto. Later, informed by Agil that a figure similar to Asuna was spotted on 'The World Tree' in Alfheim Online (ALO), Kazuto enters ALO assisted by his cousin Suguha 'Leafa' Kirigaya and Yui.

He learns the trapped players are part of a plan by Sugou to perform illegal experiments on their minds. Kirito stops the experiment and rescues the remaining 300 SAO players. Before leaving ALO, Kayaba—who had uploaded his mind to the Internet and whose real-world body had already died—entrusts Kirito with The Seed, a package program designed to create virtual worlds. Kazuto eventually reunites with Asuna in the real world and The Seed is released onto the Internet, reviving Aincrad as other VRMMORPGs begin to thrive.

Soon after, at the prompting of a government official, Kazuto investigates a series of murders in Gun Gale Online (GGO) involving a player called Death Gun. Aided by Shino 'Sinon' Asada, he participates in the Bullet of Bullets tournament and discovers the truth behind the murders. Kazuto is later recruited to test an experimental FullDive machine, the Soul Translator (STL), to help develop an artificial intelligence named A.L.I.C.E. for the Ministry of Defense.

He tests the STL by entering a virtual reality cyberspace named UnderWorld (UW), where time proceeds a thousand times faster than in the real world. However, Johnny Black injures Kazuto with suxamethonium chloride. The MOD recovers Kazuto and places him back into the STL to preserve his mind while attempts are made to save him.

Reader's Guide

Kirito is defined by his resilience and unique combat style. His signature ability involves dual-wielding swords, often combining heavy two-handed strikes with rapid one-handed slashes. Key moments include his final duel against Kayaba Akihiko to end the death game, his partnership with Asuna which grounds his emotional growth, and his battle as 'Kirito' and 'Eugeo' in the Underworld.

Did You Know?

• Kirito was born as Kazuto Kirigaya; the surname Narusaka is only his mother's maiden name and was never his legal name.
• In the anime adaptation, Kirito is voiced in Japanese by Yoshitsugu Matsuoka and in English by Bryce Papenbrook.
• In Sword Art Online Abridged, an abridged fandub, Kirito is voiced by Matthew J. Kok and given additional storylines including post-traumatic stress disorder.