Kagura, known as the Immortal Shrine Maiden, hails from the Wind Country and is a resident of the Land of Harmony. Her past is marked by profound tragedy. When a deadly plague swept through her homeland, her mother gave her a sacred, secret elixir known as the Elixir of Life, which was passed down through their family of shrine guardians. This potion granted her near-immortality and astonishing regenerative abilities. However, as a young girl, she was unable to comprehend the scope of the disaster that followed. Even as the other villagers perished and their bodies decayed, she remained convinced that they were all still alive. It was only after a wandering, rule-breaking monk stumbled upon the scene that she was forced to confront the grim reality. This encounter led her to join an organization led by a figure from the past, where she finally came to terms with her loss, but the trauma of the event caused her to lose her former cheerful disposition.

Her personality is defined by a quiet and reserved nature, often to the point of being a silent type, making it difficult for others to guess what she is thinking. Despite this reserved exterior, she possesses a strong maternal instinct and is also known to have an unexpected and somewhat quirky side, such as being seemingly gluttonous. As a student of the Rosenberg Knight Academy, she is a member of the Tenma Group, the same class as her primary charge. Her main role in the story is to protect Priecia, whom she accompanies as a guard. She is initially very dedicated to this duty, following Priecia closely, which causes friction that eventually leads to a duel between them. This confrontation ultimately becomes the catalyst for them to become good friends.

Her abilities are primarily supportive and defensive. She is an accomplished healer capable of using restorative and defensive magic. In addition to her magical skills, she is a master of archery, wielding a long bow known as Amagami-no-Mikoto as her primary weapon for combat. Her defining trait, however, comes from her consumption of the immortality elixir, which grants her an extremely powerful healing factor that makes her nearly unkillable, earning her the title of the Immortal Shrine Maiden. Information regarding her connections to other characters beyond Priecia is limited to her initial purpose as a dedicated guard. Details about any significant character development beyond her tragic backstory or how her abilities evolve over time are not available. Her personal journey concludes in some versions of the narrative with her eventually being freed from the curse of immortality and returning to her homeland to properly honor her family and fallen villagers.