Katsuya Jonouchi

Katsuya Jonouchi is Yuugi's best friend. He initially bullies Yuugi, but becomes his friend after Yuugi saves him from a more dangerous thug. He likes spending time with Yuugi and learns new games, always trying his best even when he doubts he can win.

He enters the Duelist Kingdom Tournament to raise money for surgery for his sister Shizuka, who is losing her eyesight.