Yu-Gi-Oh! 5D's episode 82: "Get With The Program, Part 2"
Kaoru is the son of Lazar and Atsuko. His face has a striking resemblance to his father's face. He seems to love his father a lot, because he never thought his father could lose. He witnessed Lazar's defeat to Crow. At first, he seems devastated, but still loves his father as he lost the Duel to protect his family from Iliaster.