Red-Eyed XaXa

At the time of the "Death Gun Incident," he was 19 years old. He was the mastermind behind "Death Gun." In the real world, he had a frail constitution and was quickly abandoned by his doctor parents after surviving SAO. In SAO, he was one of the top three members of the murder guild "Laughing Coffin," with the player name XaXa. His player name in GGO is derived from the German medical term "Sterben," meaning "death."

He started GGO on the recommendation of his younger brother, Kyouji, and became obsessed with obtaining players' personal information while wearing an invisibility cloak. When Kyouji consulted him about his character development hitting a wall, he conceived and executed the "Death Gun Incident." Initially, he was responsible for the murders in the real world, but during the third BoB, Kyouji insisted on killing Sinon in the real world, and upon learning that his hated Kirito was participating in the preliminaries, he took charge of the GGO players. In GGO, he wielded a sniper rifle for PvP, a Type 54 Black Star handgun symbolizing "Death Gun," and an estoc made from spaceship armor using his bayonet crafting skill, slaughtering many players. He was ultimately defeated by Sinon's support and Kirito's unconventional dual-wielding attack.

He was arrested following Kyouji's arrest for the attempted murder of Sinon. He left a cryptic message for Kirito through the investigators, saying, "It's not over yet." His mind remains trapped in Aincrad, and he claimed that the "Death Gun Incident" was just a game. For his behavior in SAO, refer to "#XaXa."