Jounouchi is a classmate of Yugi’s and his best friend. He bullied Yugi a lot in the beginning. He hated the fact that Yugi acted more like a child (playing with those toys) instead of a “man”. He couldn’t stand Yugi because of that. When Yugi brought the pieces of the Millennium Puzzle to school, he managed to steal one of the pieces (the central piece with the Sennen Eye). He then threw it into the swimming pool (that’s in the manga, in the anime he threw it into a canal-thingy). Yugi stood up for him and Honda when a bully beat them up. He realizes Yugi does want to be his friend after that. He also realizes that Yugi is braver and more masculine than he had given the boy credit for.
His parents divorced when Jounouchi was at a young age. He has a younger sister, by about two or three years. He lives with their father and she with their mother. He hadn’t seen his sister or his mother for years until the eye surgery. His father is an alcoholic and is constantly drunk.
Gamble (Battle City)
A gamble deck is…a gamble deck. The success of Jounouchi’s deck is dependent mainly on luck. Most of his magic cards and traps cards depend on the toss of a coin or the roll of a dice. This reflects Jounouchi’s somewhat reckless nature but also shows the confidence he has gained. This type of deck is not for the weak of heart or hesitant. He believes and that’s seems to be enough to pull him through.
Most of the monster cards in his deck are of the Warrior-class.
It is also not clear if Jounouchi had any part in Yami’s time. In the first Shin Duel Monsters game, he also appeared as Jono, a friend of the Prince’s from outside the palace.
Jounouchi and Mai share a tight relationship, despite the way they often bicker. They both care for each other greatly. Jounouchi is willing to go to any lengths for Mai, as seen by his behavior in the Battle City finals. When she is later employed by DOOM, Jounouchi can think of nothing more than how to free her. They’re not an official couple but they might as well be.
Jounouchi is your loyal sidekick of the show and the comic relief. He has been down-graded from his earlier “bad boy”/gang member role in the first few volumes of the manga. He acts stupid most of the time but he has a lot of depth underneath. He is the child of a bad divorce and hasn’t seen his mother and sister in years. Jounouchi was in a gang in junior high. He has not had it easy. He’s serious when he needs to be and doesn’t like being looked down upon.
ATK 1800/DEF 1600
Jounouchi is a fighter. He is never one to back down. He follows the code of honor of old. He fights for glory, but with honor and respect for himself and his opponents. Throughout the series, he always tries to stand up for the underdog. Whenever a player was being attacked or cheated, he is always there to gain proper retribution. It is one of the reasons why he fell so easily into Insector Haga’s trap in Battle City. This card conveys both his warrior spirit and passionate nature. Jounouchi is the “Hoono no Duelist” (Duelist of Flame) after all.
Red Eyes Black Dragon
ATK 2400/DEF 2000
It’s sort of strange that Jounouchi would have what would appear to be the complement card to Kaiba’s Blue Eyes White Dragon. While there is the shonen-ai interpretation, I shall refrain from it because I find it rather trivial anyway. I believe it to be representative of Jounouchi’s aspiration for greatness. He has always been inferior to Kaiba in one aspect or another. Kaiba is smarter (though that may actually be debatable with some out there), stronger, a better fighter, and a better duelist than Jounouchi. That is one of the reasons Jounouchi and Kaiba clash so much in the series. Jounouchi is always trying to prove himself to be just as good, if not better.