Makanakkuru is a supporting character in the story, introduced as a member of the Ainu kotan, or village, where the protagonist Asirpa lives. He is Asirpa's maternal uncle and the father of a young girl named Osoma, making him a direct relation to two central figures in the narrative. Physically, he is depicted as a well-built Ainu man of middle age, with a calm and steady presence. He has long, straight black hair that reaches his neck and a thick, unkempt beard that connects to the hair on his head. His eyebrows are notably thick, which can give him a serious look, though this is softened by his round eyes and warm smile. His traditional attire consists of a tan-colored Ainu robe, known as an attus, which features black cuffs and collar with white traditional patterns, and in colder weather, he wears a long, sleeveless fur coat over it.

In terms of personality, Makanakkuru is portrayed as a calm, intelligent, and deeply observant individual. He possesses a quiet wisdom rooted in the traditions of the Ainu people. While he is not aggressive or quick to anger, he holds strong convictions, particularly regarding the sacredness of nature and the consequences of defiling it for selfish purposes. He is also intensely protective of his family, showing a great deal of concern for Asirpa's emotional well-being following the death of her father, Wilk. He is welcoming and trusting towards the protagonist, Sugimoto, not out of naivety, but because he trusts his niece's judgment and recognizes Sugimoto's genuine character.

Makanakkuru's primary motivation is the safety and happiness of his family, especially his niece, Asirpa, and his daughter, Osoma. He is acutely aware of the emotional toll that loss has taken on Asirpa, noting that she rarely smiled after her father's death. His actions are driven by a desire to see her find joy again and to ensure she is protected, which leads him to accept Sugimoto into their community. He also appears motivated by a desire to preserve the Ainu way of life, as shown by his reverence for traditional laws and his wariness of the cursed gold that brought violence to their land.

Within the story's early arcs, Makanakkuru serves as an important source of cultural context and backstory. When Sugimoto first arrives at the kotan, Makanakkuru prevents him from triggering a deadly poisoned arrow trap, immediately demonstrating his role as a guardian of his people's territory. He provides crucial exposition about the hidden Ainu gold, explaining the belief that it is cursed because it was taken from sacred rivers, which angered the water god, Wakkus Kamuy. He also reveals the origin of the white wolf, Retar, explaining that Asirpa and her father saved him as a pup, and that the wolf was Asirpa's companion in her grief. This information helps Sugimoto and the audience understand Asirpa's complex emotional state and her connection to the natural world.

His key relationships are centered on his family. He is the brother of Asirpa's late mother, Riratte, and is the son of Huci, the eldest woman of the kotan. His interactions with Sugimoto are significant, as he serves as a bridge between the Ainu community and the outsider, accepting him partly because of the positive change he sees in Asirpa. He also develops a brief but meaningful relationship with the deserter Tanigaki, accompanying him to town to buy ammunition and offering him shelter while his leg heals. Through these interactions, Makanakkuru demonstrates a pragmatic and hospitable nature, willing to help others while always keeping the interests of his own people at heart.

The character does not undergo a dramatic personal transformation, instead serving as a stable, grounding presence within the narrative. He remains a consistent figure of support for his family. Notable abilities include his skill as a hunter, a common and essential trait among the Ainu men of his village. He is knowledgeable about traditional traps and weapons. Furthermore, he is fluent in Japanese, which allows him to act as a translator for his mother, Huci, and to communicate effectively and conduct trade with outside visitors.