Nanko is a 17-year-old detective who is one of the thirty people traveling to the mysterious Nanakimura in The Lost Village. She has a calm and somewhat detached demeanor, often appearing indifferent to her surroundings. Despite this outward coolness, she conceals considerable talent and intelligence. Her perceptions and reactions differ from those of the other characters, giving her a unique perspective on the events unfolding in the abandoned village.

Nanko is driven by a strong sense of justice and a desire to uncover the truth, even when others are reluctant to face it. She stands by her own beliefs and is willing to help her friends, showing a caring nature beneath her reserved exterior. Her clear thinking and analytical mind make her a useful asset in a group that quickly becomes fractured and paranoid. She has a few quirky habits that add to her memorable presence.

As a supporting character, Nanko does not dominate the plot but contributes to the group's dynamics by offering rational observations and occasionally stepping in to mediate or assist. Her role highlights the contrast between her composed attitude and the more volatile personalities around her. The series does not provide an extensive personal backstory for Nanko, leaving her motivations largely tied to her detective instincts and her moral compass. She does not undergo significant dramatic development compared to some other characters, but her consistent logical approach and her loyalty to her own principles make her a steady figure in the chaos of Nanakimura. Her notable ability is her deductive skill, which she uses to analyze situations and piece together clues about the village and its inhabitants.