Kirito (キリト, Kirito?) is the main protagonist of the Sword Art Online light novel, anime, manga and game series. His name, Kirito, was taken from his real name Kirigaya Kazuto (桐ヶ谷 和人, Kirigaya Kazuto?). “Kiri–” from Kirigaya and “—-to” from Kazuto. He was chosen as one of the 1,000 beta testers for the closed beta of «Sword Art Online», the first ever VRMMORPG for the NerveGear.
Kirito is someone who is not good with words, as said by Klein, and can be quite direct. This is due to him not having many friends and closing others off because of his love for computers. As such, he can come off as a rude person to others, such as Lisbeth and Sinon. Sometimes, he actually seems to enjoy angering and teasing people as well. Also, from time to time, Kirito can be quite overconfident thinking he can do things others can not.
He is almost always a calm and collected character, rarely showing any signs of distress. When Kayaba Akihiko appeared in SAO and announced that it had become a Death Game, Kirito showed only a slight reaction and was able to quickly accept the new conditions of the game, while many others panicked. He has shown different moods throughout the series; at times being rather cheerful, while being gloomy at others. When in a battle, he becomes incredibly fierce and aggressive. Sometimes, his fierceness is up to the point where he loses control of himself and is even unable to recall what he had done.