Marlene, a silver-haired elf, emerges as a pivotal rebel leader challenging the demon lord Lucifon. Known for her archery prowess and tactical cunning, she aids the protagonist by orchestrating a daring time-travel gambit: freeing a captive rebel leader imprisoned for two decades and dispatching him to reshape history. Her goal centers on compelling her younger self to fully embrace defiance against Lucifon, exploiting foreknowledge of future tragedies to tilt the conflict’s balance.

Her elven facade masks a clandestine truth—she is Ino, offspring of the demon Minakus and native to the infernal realm. This lineage binds her to Lucifon, whom she professes to love yet ambiguously opposes. A black stone, harvested from her sister Mano’s womb, serves as both tool and testament to her demonic ties. Despite her origins, she champions humanity, subtly driven by an unspoken bond with the protagonist, who later adopts the alias Eto in the past.

Marlene’s turmoil springs from her forbidden longing for Eto, a clash between her demonic blood and his divine legacy. She buries these emotions, deeming their union unthinkable. As tensions escalate, she grapples with her desires, finally embracing her yearning to shield Eto and their allies—even through mortal sacrifice. Her journey culminates in a defiant choice: betraying her demonic heritage to safeguard humanity, willingly facing annihilation to cripple Lucifon’s ambitions.

Initially a shadowy manipulator, she evolves into a frontline warrior, battling openly alongside rebels. This shift mirrors her acceptance of her fractured identity—neither fully demon nor elf—and her resolve to act despite moral ambiguities. Though she conceals her true name and motives early on, her final acts prioritize unity and survival, framing her as a complex figure straddling loyalty, love, and the inexorable pull of two warring worlds.