Anna Fugo hails from a powerful European mage dynasty and enters the GRANBELM tournament. Her childhood was defined by a close bond with Shingetsu Ernesta Fukami, an orphan adopted by her family. During this time, Anna helped Shingetsu find a shard of her family's magic stone, aspiring for them to become mages together. She personally tutored Shingetsu in Fugo magic and crafted dolls for both of them. A pivotal event saw Anna attempt a two-person spell to prove her potential as "The Witch." Unaware that Shingetsu secretly ensured the spell's success, this act planted the seeds of Anna's later overconfidence.

As she grew, Anna's initial kindness curdled into profound resentment and jealousy towards Shingetsu's superior magical talent. This shift erupted upon learning the Fugo family groomed Shingetsu as its successor, a role Anna believed was her birthright. Obsessed with surpassing Shingetsu, she abandoned former skills in sewing, studying, and cooking. Pride, aggression, and cruelty defined her personality, her envy manifesting physically as scorching heat. She often submerged herself in ice baths for relief, though her fury could boil the water.

Born under a star that denied her innate magical power, Anna possesses notably low magical ability. She compensates with her Armanox, Aconite Gris—a regal, red mecha supplying vast energy. She specializes in her family's temperature-control magic, manipulating fire and ice. Her combat style relies on strategic spell traps and decoys called "Embers," which fight in her stead.

Within GRANBELM, Anna relentlessly targets Shingetsu, commanding subordinates Suishou Hakamada and Rosa. Noticing Mangetsu Kohinata's unexpected entry, she dispatches Rosa to capture her. After Rosa's defeat and loss of her magic stone, Anna coldly expels her from the Fugo residence. In later rounds, Anna repeatedly ambushes Shingetsu, exploiting Viola Katze's prior damage. Her confrontations turn increasingly barbaric, fueled by rants about others favoring Shingetsu. She survives rounds via tactical retreats but struggles against faster Armanox like Setsgetsu Baika.

Anna's relationships are hostile and manipulative. Her fixation on Shingetsu borders on madness, leading her to publicly slap Shingetsu and spew vitriol during battles. She rules servants authoritatively, threatening violence for disobedience. Her interactions with Suishou are especially strained, as Suishou openly defies her upon recognizing Anna's magical weakness.

Anna faces elimination in GRANBELM's third round after a decisive defeat by Shingetsu. Following this loss, her existence is erased from reality, causing non-participants to forget her entirely. In the reconfigured timeline, Rosa becomes the Fugo family's elder daughter. Moments before erasure, Anna briefly learns her mother's original intent: to shield her from magehood's pressures, a realization arriving too late to alter her self-destructive path.