The character known as Mother in the anime Dororo is Nui No Kata, the former Lady of Ishikawa and the wife of the feudal lord Daigo Kagemitsu. She is the biological mother of two sons: Hyakkimaru, her firstborn, and Tahomaru, her younger son.

Her background is defined by a traumatic and morally fraught event. When Hyakkimaru was born, his father sacrificed him to forty-eight demons in exchange for power and prosperity over their war-torn domain. Horrified by her husband's pact and the resulting state of her infant son, who was left missing limbs, facial features, and internal organs, Nui No Kata intervened to save him from execution. She set the baby adrift on a river, an act that ultimately led to his rescue by a medicine man named Jukai. This decision haunted her for years, and she spent much of Hyakkimaru's absence praying daily for forgiveness before a headless Buddha statue.

In terms of personality, Nui No Kata is defined by her deep compassion, gentleness, and strong moral conscience. She is the only member of her immediate family who openly regrets the loss of her first son. Unlike her husband, who remains ruthless, and her younger son, who is initially loyal to their father, she carries the weight of the sacrifice with immense sorrow.

Her primary motivation is maternal love and the desire for redemption. She is driven to make amends for Hyakkimaru's suffering and to find him after he returns to reclaim his body. This desire is so powerful that she ultimately renounces her status as a lord's wife, effectively betraying her husband and her former life, in order to side with Hyakkimaru.

In the story, Nui No Kata serves as a quiet but crucial moral counterpoint to Kagemitsu's ambition. She is a supporting figure who provides Hyakkimaru with the truth about his past and helps guide him on his path. She joins the young thief Dororo in the search for Hyakkimaru, choosing her son's well-being over her noble role.

Her key relationships are with her two sons and, to a lesser extent, her husband. Her bond with Hyakkimaru is built on profound guilt and unconditional love; she sacrifices everything simply to be near him. Her relationship with Tahomaru is more complicated. She realizes late in the story that she never gave him the attention or love he needed, so focused was she on the trauma of losing Hyakkimaru. This neglect is a significant source of regret.

Over the course of the narrative, Nui No Kata undergoes a tragic but redemptive development. She transitions from a passive, grieving noblewoman into an active agent willing to abandon her entire world. Her ultimate act is one of final atonement. During a devastating fire in the family's castle, she decides not to escape. Recognizing that Tahomaru is dying, and acknowledging the neglect she showed him, she chooses to stay with him, holding him as they perish together. This act is presented as her way of finally giving him the love she withheld.

Nui No Kata does not possess combat or supernatural abilities. Her notable traits are her emotional resilience and her capacity for self-sacrifice. Her power comes from her unwavering love and her willingness to surrender her social position, her family ties, and ultimately her life, to fulfill her role as a mother to both of her sons.