Fortuna (フォルトナ) was the Guardian of Seal in the Elior Forest and was Emilia's aunt on her father's side. Roughly a century before the events of the main story, she took care of young Emilia instead of her parents.
She was repeatedly brought up during the events of Arc 4, until she officially debuted in Emilia's First Trial, in the Arc's climax. Having been the person Emilia was close to the most throughout her supposed childhood, she plays a pivotal role in Emilia's character arc as she greatly influenced the young half-elf's view of the world. She was killed by Petelgeuse Romanée-Conti, after he was deceived by Pandora.
Fortuna was a beautiful woman with a fit physique whose glistening silver hair was cut fairly short. Her almond-shaped violet sanpaku eyes, that looked similar to Natsuki Subaru's, glistened like gemstones and were sharp and intimidating. As an elf, her ears were abnormally pointed. In her hair, Fortuna wore a silver hairpin shaped like a four-petaled flower. After Fortuna's death at the hands of Geuse, Emilia took to wearing her pin so she could always have a part of her beloved mother with her.
Like every elf in Elior Forest, Fortuna wore clothing that was primarily white and violet. Her outfit, which prioritized ease of movement, consisted of a sleeveless skin-tight violet unitard, white knee-high boots with violet soles, a band consisting of identical white flowers on her right thigh, and a white cold shoulder jacket with violet edging that went down to her waist and was open below the breasts. A golden brooch in the shape of a pair of open wings was affixed to her collar.
In The Second Trial, See the unimaginable present, Fortuna wore a white sun hat with a light blue band and a long dress in a similar style to her usual outfit.
As an elf, Fortuna had an unspecified lifespan that far surpassed a human one. At the time of her death, she had lived for at least over a century yet still maintained the physical appearance and athleticism of a young woman.
Fortuna was a kind-hearted and modest woman who cared deeply for her loved ones and would give anything to protect and nurture them. She seemed to have low self-esteem, as she routinely understated her positive features. As a result of her pessimistic outlook on herself, Fortuna became easily flustered by compliments given to her by her loved ones, particularly Geuse. In a weak attempt to hide her embarrassment, she would usually admonish the person who complimented her and act as though she was angry with them. Despite her self-esteem problems, the elven woman was courageous in battle, refusing to yield even if she stood no chance of victory and would die as a result of her failure.
Fortuna was an elven woman whose brother married a human woman and bore a half-elven girl named Emilia. However, after her brother and sister-in-law mysteriously disappeared, Fortuna took Emilia in and raised her as her own daughter. At some point, the pair moved into an elven village in the Great Elior Forest where they were warmly welcomed. Emilia, for unclear reasons, was of paramount importance and as such was protected by the villagers. The settlement would occasionally receive supply deliveries from Geuse Romanée-Conti and his Witch Cult underlings. Fortuna and Geuse shared a long history and both had unspoken feelings for the other.
One day, the village was attacked by radical members of the Witch Cult led by the Sin Archbishop of Greed Regulus Corneas as well as Pandora. After ordering Archi Elior to evacuate Emilia from the forest, Fortuna attempted to defeat Regulus and Pandora alongside Geuse. The Witch of Vainglory was able to separate herself from the fight and catch up with Emilia, who herself had already been separated from Arch. When Geuse and Fortuna arrived on the scene, Pandora was able to use her power to trick Geuse into killing Fortuna using the invisible hand, Fortuna died in the arms of Emilia, who subsequently froze the entire forest in her rage. Petelgeuse Romanée-Conti, driven insane by his accidental actions, joined the Witch as she left the frozen forest
Magic User (魔法使い Maho Tsukai): Most people were only able to use spells from only one of the six magical elements, with Fortuna being connected to the element of fire. Fortuna was an extremely strong Fire Magic user. She's one of the five most powerful Fire Magic users in the entire series. Fortuna was able to perform powerful ice spells with her vast reserves of mana.
- El Huma (エル・ヒューマ): The user forms and shoots multitudes of ice spikes from their hands which easily pierce through human flesh and immediately vanish after impact.
- UI Huma (ウル・ヒューマ): By freezing the air around her, Fortuna could produce large amounts of sturdy ice that she could then telekinetically direct.
- Al Huma (アル・ヒューマ): A bit different from the standard version of a spell, Fortuna summons a giant ball of ice so large as to encompass the entirety of the visible sky to crush her foes.
- Ice Weapons: Possibly the reason for Emilia learning Ice Brand Arts (アイスブランドアーツ), Fortuna was able to form weapons out of ice, such as swords and spears. They were sharp enough to easily cut Pandora in half.
- Fortuna and Geuse's relationship span across a long period of time. During that time, Geuse changed many bodies, at some point even using a female body. Despite that, Fortuna's feelings for Geuse never changed.
- In episode 43 of the anime adaptation, Fortuna erroneously chanted Al Fula (the name of a wind magic spell) when using Al Huma against Regulus Corneas.
- Fortuna and Petelgeuse's Japanese voice actors also voice Yuuki Asuna and Kirigaya Kazuto, a well known and popular couple from the anime series Sword Art Online, respectively.
- Fortuna can be seen sporting an insignia in shape of a golden eagle, just under her neck. It looks almost exactly the same as House Roswaal's very own insignia, which the consecutive matriarchs tended to use to mark what is and was theirs.