Aht is a young woman and a warrior from the Kusharundo clan, where she holds the rank of princess. She is first introduced dressed as a man to fight on the front lines alongside her elder brother, whose name is Klato or Kratt. Her primary motivation for the first part of her journey is revenge, as she seeks to kill the swordsman Köinzell for the death of her brother. Her brother was transformed into a monstrous creature, and his death at Köinzell's hands was ultimately an act of mercy, a truth that Aht is initially unable or unwilling to accept.

Aht's personality is defined by a fierce sense of determination and a reckless bravery that often puts her in perilous situations. Her quest for vengeance is driven by a deep respect and admiration for her brother, whom she looked up to greatly. This single-minded pursuit, however, evolves over time. As she repeatedly fails to defeat Köinzell due to her inferior swordsmanship, she is forced to confront the reality of what happened. She eventually comes to accept that Köinzell's action was not a murder but a necessary mercy, and this realization transforms her hatred into a profound respect for him.

Following this shift, Aht becomes a devoted ally and companion to Köinzell. Her role in the story changes from an adversary to a supporter, as she strives to gain his acceptance and prove her worth. This devotion is so strong that it leads her into reckless battles. During one such fight, she is mortally wounded. In a desperate act to save her, Köinzell gives her his own blood, which is a mixture of human and fairy blood. This transfusion heals Aht and transforms her into a human-fairy hybrid, granting her new abilities but without the pointed ears that characterize Köinzell's fairy features. Her key relationships are therefore centered on her brother and on Köinzell, who becomes both the object of her initial revenge and later the person she is most loyal to.

Her role in the broader story is that of a steadfast fighter and companion. She rejoins battles even when injured, determined to show that her devotion makes her an asset rather than a hindrance. While her most notable abilities stem from her swordsmanship and warrior training, her most significant power is acquired later as a result of her transformation, which grants her the regenerative and other enhanced traits of a human-fairy hybrid. Her character development traces an arc from a vengeful sister to a loyal, if recklessly brave, ally whose personal quest for atonement and approval becomes intertwined with Köinzell's own larger journey.