Hiana is a character who appears exclusively in the live-action film adaptation of Attack on Titan. She is a new recruit of the Scout Regiment, the military branch that ventures outside the walls to fight Titans. Her precise background before enlisting is not extensively detailed, but it is known that she is a single mother with a young daughter named Riko. Her primary motivation for joining the dangerous Scout Regiment is a pragmatic one: to receive child support and financial aid to provide for her daughter. This decision forces her to say a tearful goodbye to Riko, from whom she is then separated.

In terms of personality, Hiana is depicted as a caring and devoted mother, with her daughter being the central focus of her actions and her final thoughts. She also displays a curious nature, which leads her to wander away from her squad to investigate a sound she believes is a crying baby, a decision that ultimately has fatal consequences. Another facet of her personality is shown in her interactions with Eren Yeager. She appears to develop a crush on him, displaying a lighthearted, teasing side as she jokes with him and attempts to console him when he is distressed. This culminates in an attempt to seduce him, an act that suggests a desire for connection or comfort in the face of the grim reality of their world.

Hiana's primary role in the story is to serve as a companion and momentary love interest for Eren during a key sequence. She finds Eren after an emotional confrontation, quiets his screaming, and leads him to an abandoned building to hide for the night. In this shelter, she tries to learn about his relationship with Mikasa and shares her own reason for joining the military. Her most significant narrative function occurs during her death scene. As she attempts to seduce Eren, a Titan suddenly breaks into their hiding spot, grabs her, and swallows her whole. Her final word is her daughter's name, Riko. Her death is not just a tragic end but a pivotal moment for Eren. After he is swallowed by a different Titan, he finds Hiana's partially dissolved corpse inside the creature's stomach. The horrifying sight of her mutilated body, combined with the burning sensation of the stomach acids, fuels his rage and despair. This emotional breaking point directly triggers his transformation into a Titan shifter, allowing him to burst free and kill the Titan, thereby avenging her.

Hiana's key relationships are limited but deeply felt. Her bond with her daughter, Riko, is the most defining aspect of her character, driving her decision to join the military and coloring her final moments. Her relationship with Eren Yeager is also central; she is kind to him, attempts to offer comfort and romantic attention, and her gruesome death, witnessed by him, becomes the catalyst for his awakening as a powerful Titan shifter. She has no notable abilities, as she is portrayed as a new and inexperienced soldier who is killed soon after her introduction.