Fiona, whose full name is eventually revealed to be Elisi Linette, is a central figure in the narrative as a young woman of the Ancient Zoidian race. She is discovered in a state of suspended animation by the protagonist Van within a ruin, having been preserved for an unknown length of time alongside the organoid Zeke. Upon awakening, she suffers from complete amnesia, possessing no memory of her identity, her past, or the circumstances that led to her being placed in stasis. The name Fiona is given to her by Van after she utters the word upon first meeting him.

Her defining motivation is the search for a legendary location known as Zoid Eve, a concept she vaguely recalls that is believed to be the origin of all Zoids on the planet Zi. This quest is deeply personal, as she hopes that finding Zoid Eve will unlock her lost memories and reveal her true heritage. As the story progresses, her past slowly resurfaces, confirming her identity as an Ancient Zoidian, a near-extinct race with a profound, intrinsic connection to Zoids. Her character arc involves a transition from a fragile, naive girl to a more mature and knowledgeable individual, eventually becoming a capable field research assistant to the scientist Doctor D.

Fiona's personality is marked by a gentle, kind, and caring nature. In the early part of her journey, she displays significant naivete and an airheaded quality, often failing to grasp common knowledge or recognize danger, which can lead to humorous situations. She is, for instance, known for her peculiar fondness for salt, frequently adding large amounts of it to her food and coffee. Despite her initial innocence, she possesses a strong inner resolve and a pure heart, traits that often inspire and soften those around her. She is also shown to become quite territorial and jealous regarding Van's attention from other girls, hinting at her deep affection for him.

Her role in the story is primarily as a companion and emotional anchor for the hero Van, as well as a key to unlocking the mysteries of the planet's past. While not a frontline fighter, she contributes with her growing scientific acumen and her unique Zoidian abilities, which include telepathically communicating with organoids like Zeke and other Zoidians. In a pivotal moment, she uses these powers in conjunction with Zeke to help evolve Van's Shield Liger into the more powerful Blade Liger. Her Zoidian heritage also grants her significantly enhanced senses, allowing her to hear and smell water from great distances or spot minuscule errors in a loom's thread count from a glance. On the rare occasions when she pilots a Zoid herself, she is most often seen operating a Pteras.

Her most significant relationship is with Van, which develops from a partnership of convenience into a close bond with clear romantic undertones; she is often seen worrying for his safety, and it is suggested that they become an item as the series concludes. She shares an exceptionally close, almost symbiotic connection with the organoid Zeke, as they were found together and share a psychic rapport. The experienced mercenary Moonbay acts as an older sister figure to Fiona, guiding and protecting her, while the lone wolf Irvine develops a protective, brotherly affection for her. She remains consistently oblivious to the romantic feelings that the young man Thomas harbors for her, viewing him merely as a friend. Her relationship with the antagonistic Zoidian Reese is one of rivalry, with Reese often lashing out at her physically and emotionally.