Jonouchi is Yugi's best friend. At the beginning Jonouchi used to bully Yugi but after being saved by Yugi from an even more of a dangerous thug, Jonouchi has been pals with Yugi ever since. Jonouchi likes to hang around with Yugi and learns a lot of new games. He's not always confident that he'll win his games but he always tries his best. He enters the Duelist Kingdom Tournament to get money for his sister, Shizuka, who is losing her eyesight. He wants to use the money for her surgery.
