Born into a strict military clan, Soiya Fen was trained from early childhood to become a living weapon. She serves as an elite assassin in a spiritual military organization, specializing in silent eliminations and covert operations. Soiya believes emotions are liabilities and suppresses them completely, relying only on discipline, precision, and absolute control. Her presence is quiet but oppressive — enemies often realize she is there only moments before it is too late. Though she appears distant and merciless, her loyalty to her duty and comrades is absolute.