Natsume Kagiya is a member of the Sakurai Kikan, a covert Japanese spy organization operating in Shanghai in 1931. He was born into a family of poor farmers and spent his youth working as a servant at a garden treehouse, where he first discovered his psychic ability. His powers grant him augmented eyesight, functioning like a telephoto lens; he can see distant objects with clarity, possesses night vision, and his sight is especially acute during moonlit nights. Natsume joined the Sakurai Kikan primarily to protect Yukina Sonogi, a fellow agent and his charge. In public, their relationship is formal to maintain appearances, but privately they treat each other as equals, with Natsume remaining deeply loyal to her. His personality is described as stern yet quietly earnest, honest, and sincere, though he occasionally has clumsy or klutzy moments. He serves as the team's surveillance and reconnaissance specialist, often providing critical visual intelligence during missions. Over the course of the series, Natsume's development is tied to his growing bond with Yukina and his increasing confidence in using his abilities in high-stakes situations.