Fumi Aoyama, born Fumi Tanigaki, is a minor character in the narrative, primarily existing within the backstory of another character. She was an Ani Matagi and the younger sister of Genjirou Tanigaki, a former member of the 7th Division who becomes a key ally to the protagonist. Her life is defined by her origins in the Matagi hunting community of the Tohoku region, a group of traditional winter hunters with customs similar to the bear worship practiced by the Ainu people. Fumi eventually married Kenkichi Aoyama, a friend of her brother, and left her family’s village to live with him.

The details of Fumi’s personality are not explored, as she is a figure from the past who never appears in the main storyline. Her significance is almost entirely tied to the tragic circumstances of her death, which serves as a powerful motivating force for her husband. After she fell seriously ill with smallpox, her husband Kenkichi was faced with a terrible choice. Knowing that families would often abandon ill relatives to prevent the spread of infection, he could not bring himself to leave her. However, Fumi refused to let him die alongside her, believing he should live on if he did not catch the disease. To prevent the infection from spreading to her own family, who would surely come looking for them, she asked her husband to kill her and then leave the village. Kenkichi, heartbroken, euthanized his wife using a method he knew well as a hunter.

This event shattered Kenkichi Aoyama’s life. After setting fire to their house and leaving Fumi’s masuke knife behind, he fled the village and eventually joined the Imperial Japanese Army. Fumi’s role in the story is therefore that of a tragic catalyst. Her death created an enormous sense of guilt in her husband, who carried the burden of her story and his actions for the rest of his life. He later confided this painful memory to a dying comrade, unknowingly telling the story to his brother-in-law, Genjirou Tanigaki. This revelation allowed Tanigaki to finally learn the truth of what had happened to his sister and understand his friend’s long-held secret. As a result, Fumi Aoyama’s legacy is not one of personal action, but of deep emotional impact on the men who knew her, driving their motivations and shaping their sorrowful pasts. No further information is available regarding her appearance or specific abilities.