Joey Wheeler, known as Katsuya Jounouchi in the manga and Japanese version, is a Yu-Gi-Oh! character and is best friends with Yugi Muto.
Jonouchi and his sister, Shizuka, were separated when their parents divorced. Shizuka was brought by her mother while Jonouchi lived with his father. Jonouchi lived in poverty, due to his father's gambling addictions and alcoholism. Jonouchi became a street thug and hung out in Hirutani's gang for long periods of time when he is in middle school. He often got into fights and developed great fighting skills. He also hung out with Hiroto Honda, who was not in Hirutani's gang. Jonouchi used to pick on Yugi at school. He was annoyed by how Yugi would let himself get pushed around and claimed his bullying was teaching Yugi how to be a man and even offered Yugi to punch him back, although Yugi hates violence. He once teased Yugi by taking his box, containing the Millennium Puzzle and secretly stealing a piece. Honda tried telling Jonouchi to stop, but Jonouchi just mocked his custodian position. Anzu Mazaki took the puzzle box back and called Jonouchi bully. To escape from Anzu, Jonouchi left with Honda as he went to queue for Miho Nosaka's lunch. In the hallway, Ushio overheard Jonouchi mentioning bullying and asked what was happening. Jonouchi tried telling Ushio to stay out of it, but was restrained by Honda, who wanted to avoid trouble. Afterwards Jonouchi showed Honda the piece of the puzzle he had taken and threw it out the window into a canal The next day Ushio beat-up Jonouchi and Honda, under suspicion that they were bullying Yugi. However Yugi objected and insisted that Jonouchi and Honda were his friends. On the way home, while he spoke with Honda about Ushio, Jonouchi remembered how Yugi had stuck up for him and recovered the piece of the puzzle from the canal. He then saw Ushio attacking Yugi. Jonouchi gave the piece of the puzzle to Yugi and he and Honda tried fighting Ushio off, only to get beaten-up again. However Yugi finished the Millennium Puzzle, while the three of them were barely conscious and changed to Dark Yugi, who defeated Ushio in a Shadow Game. The next day Jonouchi answered Yugi's "Something you can show, but can't see" riddle, saying it's friendship and that they're friends. Jonouchi noticed how Anzu was acting odd, after avoiding walking home with them a few days. He initially assumes she's dating older men for pay. Miho Nosaka and later Honda investigated by followed Anzu home. Seeing them leave with Anzu the next two days, Jonouchi and Yugi followed the three of them, finding they had all gotten jobs at Burger World. There were two escaped convicts and Jonouchi assisted in identifying the first, by checking the customer's legs for a calf wound after they spilled a basket of toy cars, pretending it was an accident.
Joey started out as a bully, but becoming friends with Yugi Muto changes this. Though occasionally portrayed as comic relief, he is essential to the plot and the series' overall theme. He is an enthusiastic duelist, who claims dueling is about fighting to help people you love. Kazuki Takahashi considers Seto Kaiba and Yami Yugi weak in comparison to Joey. The first syllables of Yugi and Jonouchi's names form Yūjō, which is Japanese for friendship, symbolizing the bond between the two characters. The card "Yu-Jo Friendship" is based on this connection.
Joey's character design was overseen by Kazuki Takahashi.
In the first seven volumes of the original Yu-Gi-Oh! manga, Joey's hairstyle changes drastically. Originally featuring two large fringes in front of his ears, the hairstyle changes to a sporadically arranged taper-like and unrealistic hairstyle. Joey's first color appearance depicts him with medium brown hair and black eyes. Subsequent appearances lighten the hair color to dirty blond and blond. His eyes are portrayed as brown or hazel. In the first series anime, Joey's hairstyle does not change, and the sporadic hairstyle colored in a bright blond style is used. His eyes are brown. In the second series anime he has dirty blond hair in the sporadic hairstyle and dark brown eyes. His usual outfit from the second series anime consists of a long green open jacket with a raised collar, a white T-shirt underneath and blue jeans. Later in the series, his green jacket is replaced with a blue denim one. He often carries a KaibaCorp Duel Disk on his left arm.