Suzune Rokuoin is the sole daughter of the Rokuoin family, a lineage celebrated for producing generations of Vanguard professionals. Though still a middle school student, she is already a recognized professional cardfighter and one of the Three Rising Stars in Vanguard, alongside Raika Koshiba and Senka Kanae.

She has light green hair and light green eyes, and she rarely displays emotion, a trait that has earned her the public nickname "Vanguard Machine." She is always seen carrying a large jar of caramel candies, her favorite food.

The Rokuoin family has a storied history in the world of Vanguard. Suzune's mother, Yurine, was a professional who could not fully develop her own talent and faced years of quiet criticism. After giving birth to Suzune, she retired from professional competition. Recognizing her daughter’s innate potential, Yurine provided Suzune with rigorous training that propelled her into the professional Vanguard world.

The character's insert song is titled "Titi Mivans."