Sword Art Online 21 (light novel)

READ THE NOVEL THAT IGNITED THE PHENOMENON!A year has passed since Kirito and Asuna's return from the Underworld. With them is Alice, who has been given a physical body. But their peace is quickly broken when the three are suddenly thrust into an unfamiliar game, Unital Ring. This new world is a survival MMO that fuses together every VRMMO created with the Seed program. As soon as it starts, Kirito finds himself with nothing but his underwear. Now, he's got to challenge a mysterious VRMMOSVG under desperate circumstances!