The daughter of the Mayfield noble family from Iglesias, a cold country in the north of the continent. Her father was ruler of Fandelcia, a city in east Iglesias. She was raised sheltered as a lady, therefore she is naively ignorant of the ways of the world, and full of pride. She is hot-tempered and has an unyielding spirit. Once she decides something, she dislikes turning from it.
Crevanille and Remus briefly met her at their first time in Marquelay while talking with a merchant named Porak. Eliza asked Porak if her requested item was in stock. She appeared as a graceful, refined young lady with long hair.
Later, she rescued Crevanille's party when they were shipwrecked after escaping Dulkheim by boat. She took them in to live at her villa in Marquelay. Due to the war, she stayed at her villa in Marquelay for safety. She would generously offer shelter to all new allies recruited.
Christopher informed her that the city of Fandelcia, which her father governed, had been taken over by Dulkheim. Worried about her parents whom she hadn't heard from in a while, she wanted to travel to Fandelcia with Crevanille as a bodyguard. On the way they stopped at Ordinale mansion to visit Alfonse, and he refused to let her go to Fandelcia insisting it was too dangerous. This angered Eliza, and she cut her hair short, changed her formal dress, and revealed her own weapons. She refused to be a burden that needed protection and was determined to fight for herself. Alfonse agreed to let her go, and Christopher accompanied them to Riesel. In Riesel, Christopher had a ship to take the party to Iglesias. Eliza knew of another way to get back once they were in Iglesias.
In Fandelcia, Eliza was angry at seeing her house taken over by Dulkheim. She talked to citizens to find out where her parents were. Meanwhile, Crevanille and Remus reunited with Lumis and Bauer in the mansion. Eliza learned that her father had escaped the city and would eventually get in touch with her Marquelay.
From then on she accompanied Crevanille's party to fight in battles against Valkania and Dulkheim, and to save the world from the danger of summoning.
Because Eliza's Marquelay villa stopped receiving money from Mayfield, Eliza's butler Levan dismissed all of the servants because they couldn't be paid. Eliza burst in anger at him and secluded herself in her room. Crevanille reasoned with her and she understood the circumstances. Concerned about the finances, she tried to find a way to make money herself. Her ideas were shot down by Sydney and she became frustrated. Finally she came up with an "odd jobs" business where she would solve requests from clients. She succeeded at a few private investigation jobs.
Eliza learned that her father was starting up an underground faction to overthrow Dulkheim's control of Fandelcia. She requested Crevanille to help save her father from a plot by Dulkheim. In Fandelcia, they fought Cargill and rescued her father. She convinced him to stop trying to reconquer Fandelcia, because the citizens were safe after all and didn't care who the ruler was if things were still the same. Eliza's parents were proud of her for becoming independent and mature from a sheltered girl who never before had to know work.