Natsuki Seba is a supporting character in the manga and anime series 'Sakamoto Days.' He is a member of the Order, an elite group of assassins. Seba is known for his intelligence and technical skills, often handling information analysis and support roles within the team. While not as physically imposing as other assassins, his resourcefulness and quick thinking make him an invaluable asset. Seba's calm demeanor and strategic mind help the protagonists navigate dangerous situations throughout the series.