Kirigaya, born Narusaka Kazuto and also known by his avatar name Kirito and by his title, the Black Swordsman, is the main protagonist of the Sword Art Online franchise.

His avatar name, Kirito, was taken from his real name Kazuto Kirigaya; "Kiri--" from Kirigaya and "----to" from Kazuto. He was one of the 1,000 beta testers for the Closed Beta of Sword Art Online, the first ever VRMMORPG for the NerveGear Head Gear system. In the virtual world, he is a Swordsman of godlike strength.