Sword Art Online is a Japanese light novel series written by Kawahara Reki and illustrated by abec.
In the year 2022, Kirito, a solo player who had the luck-of-the-draw to play the beta version, and the many other players of Sword Art Online (SAO) are trapped inside of a game, unable to logout; the only way to live is to win. Death in-game means death in the real world; tampering with or prolonged power outages to the Nerve Gear, the gear that simulates in-game character control by redirecting brain signals, also means death. To win means to defeat the final boss on the top floor; out of the original 10,000 players at the start, two years later, over 6,000 remain with 26 floors left to clear.
Below are the characters found available on the site that cosplayers have depicted.