Kōsei Hida was originally a free agent hired by Meifon Li's grandfather, Chenho Li, to serve as an advisor and support for Meifon after Chenho's death. He works as Meifon's left-hand man and is responsible for overseeing various departments within the Links Group, including payroll and other administrative tasks. On the ship, he typically takes a passive role as Meifon's advisor and occasionally prepares tea, even during minor skirmishes. He is generally well-mannered, reliable, and strives to handle matters in a just and timely fashion. His calm and composed demeanor makes him a steady presence among the crew. Kōsei is motivated by a deep sense of loyalty to Meifon and the memory of her grandfather, which explains his unwavering willingness to assist her in all situations. He often finds himself being pushed around by Meifon's headstrong personality but remains supportive nonetheless. In combat, Kōsei does not frequently participate, though he possesses some proficiency with firearms and has been involved in battles when necessary, such as defending against bio-androids. His key relationships include his close working dynamic with Meifon and his prior service to Chenho Li, which established the foundation for his role. Throughout the story, Kōsei remains a consistent and dependable figure, providing logistical and moral support as the crew faces challenges.