|Nickname:||Chazz Princeton, Manjoume Thunder, The Chazz|
He is initially portrayed as an antagonist but eventually serves as one of Yuki Judai's rivals throughout the series. However, it is revealed early in the first season of the series that his elitism stems from his older brothers who urge him to become a great duelist in order to have their family reign over the dueling world, as his brothers rule over the political and financial worlds. After becoming estranged with his brothers, Jun decides to pursue a career in dueling without their help. It is revealed that Jun has a soft side in the second season.
His self-imposed nickname in the English version is "The Chazz" while his Japanese nickname is "Manjoume Thunder", which is spawned from the phrase "It's Manjoume-san!" ("Manjoume-san da!"). In the manga, Jun is a more serious character than his anime counterpart, and his main spirit card is Light and Darkness Dragon.
Voiced by: Taiki Matsuno (Japanese), Tony Salerno (English, 1-89), Marc Thompson (English, 90 onwards)