The main character, Tsukasa (TV series)/Shugo (Legend of the Twilight TV/Manga), is sucked into this popular, new interactive roleplay game called "The World." The strange thing is, Tsukasa/Shugo has no idea how he got there - in fact, he can't remember anything about himself at all. Eventually he meets up with some fellow players, who soon come to realize that our main character has a bit of a problem socializing. Oftentimes they would wonder why he was so rude, and throughout the series, his friends try to understand him, and eventually they all try to help Tsukasa/Shugo to get out of this game and back to "himself" in the real world. Thus, they begin a battle against the mysterious character/virus/program glitch that brought him there in the first place...