Nikola, a male soldier in the Althea Royal Guard and subordinate of Davi, conceals the true identity of Firenda—a master manipulator whose origins stem from a childhood marked by orphanhood and physical unattractiveness. Consumed by envy, she murdered a wealthy girl named Firenda, stole her identity, and began systematically seizing beauty, happiness, and resources from others, driven by a warped desire to erase what she lacked.

As Nikola, Firenda infiltrated the Royal Guard as a spy, rising to second lieutenant of the Special Service. Her abilities in face alteration and environmental illusion enabled espionage, including delivering false intel about the "Abyss Demon" and manipulating Tokikaze Sakai by drugging him to awaken his bloodlust. Her schemes spanned centuries: as an instructor at the 13th Special Military Forces School, she collaborated with Schmelman Bach on the "Aerial Ace Project," experimenting with genetic modifications to engineer superhumans. Jealous of Schmelman’s bond with his adoptive son Sakai Rihito (later Licht Bach), she manipulated Schmelman’s psyche and forced Rihito into becoming a test subject. Later, she cloned Schmelman and Class A students, triggering chaos during the Abandonment War and influencing the sky island Althea’s creation.

In the present, Firenda assassinated King Charles De Bergt Althea XI, framed Licht as a traitor, and eliminated Clone Schmelman after exploiting him. During the Last War Arc, she commanded Special Service forces against adversaries like Jail Murdoch and clashed with Hina, whose inherited purity from Tsukina Farrow she coveted. Her count of 47 symbolized stolen traits and lives, reflecting her nihilistic creed that weakness justified destruction. In her final confrontation, she revealed her history of theft and manipulation, challenging Licht and Hina’s ideals before facing defeat, her philosophy of exploitation collapsing against their resolve.