Asuka Tenjouin is a strong female Duelist from the Obelisk Blue dormitory at Duel Academy as well as one of Juudai's closest friends. She usually serves as the only female protagonist in Yu-Gi-Oh! GX, although Rei begins having a slight role as well near the end of the series. She's older brother is Fubuki Tenjouin.
An alternate universe version of Asuka appears in Yu-Gi-Oh! ARC-V.