Futaba Morishima, also known as Fiona Ryder, is a main character originating from Earth. She possesses exceptional racing abilities that fuel her popularity within the racing community. Her personality is cheerful, vivacious, and determined, marked by a refusal to flatter others. This trait sometimes sparks conflicts with protagonist Kazuya, yet she simultaneously acts as a peacemaker within her group.

As the only female member of the Junior Earth Team (JET), she pilots the Mach Shark, a highly advanced machine symbolized by a white jaguar with black spots. She utilizes this vehicle strategically during races to gain advantages. Demonstrating strong competitiveness and a drive to excel, she often pushes herself to her limits. Despite this fierce nature, she exhibits deep loyalty to friends and teammates, frequently supporting and motivating them even at potential cost to her own victory. This loyalty aligns with traits associated with Enneagram Type 6w7, emphasizing a desire for security and support within her team.

Interpretations suggest she may exhibit traits of the INFP personality type, characterized by introspection, a strong moral compass, and standing up for her beliefs and friends, while other analyses propose the ISTP type. Her presence is a significant factor in the team's dynamics and overall success.