Freyja serves as the main antagonist of Book IV in Fire Emblem Heroes. She's a Dökkálfar and rules Dökkálfheimr, the realm of nightmares.
As a child, Freyja was bullied relentlessly over a mark beneath her nose. Her brother Freyr was the only one who showed her kindness during those years, which shaped everything about her. Even as she grew into her beauty and attracted suitors, she rejected them all—Freyr remained the sole focus of her devotion and affection.
The experience left her fundamentally different from her brother. While Freyr mourns what happened to humanity when they were transformed into ljósálfr and dökkálfr, stripped of their mortal lives, Freyja feels no remorse about it. She views the transformation as necessary to save their world, and now sees humans as little more than tools to be used for her own purposes. Her childhood trauma twisted what once was a timid, compassionate nature into something far colder.
Because Freyr alone protected her when no one else did, Freyja became willing to do anything for him—her admiration for her elder brother became absolute, driving nearly everything she does.
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