Fiona Ryder serves as a main character and member of Team J.E.T. After training at Earth's Scan2Go Training Facility under Coach Ray, she embarked on a racing career across the universe piloting her vehicle, Leopatra.

She possesses orange hair featuring a prominent strand resembling a tail, cyan eyes, and pale skin. Her signature attire includes a white vest with pink accents over a pink dress marked by yellow lines, paired with short grey sleeves. She wears white skinny pants, white boots featuring pink cuffs and soles, and ruffled white fingerless gloves. A yellow bracelet adorns her right wrist.

Fiona displays a personality marked by arrogance and pride, refusing to flatter others. Despite this, she exhibits notable liveliness and determination. As the sole female member of Team J.E.T., she sometimes clashes with teammate Kazuya but also acts as a peacemaker within the group. She travels with her pet, Toto.

Debuting in the series' first episode during Team J.E.T.'s inaugural race, Fiona appears consistently throughout all 52 episodes. An alternate version, designated Fake Fiona Ryder, appears in episode 38. This iteration belongs to Fake Team J.E.T. and pilots the Fake Infinite Leopatra. This variant exists exclusively within the anime continuity and has no representation in associated toys or games.