Nui was once the lady of Ishikawa and the former matriarch of the Daigo Clan until she abandoned her statuses when she divorced her marriage ties with Kagemitsu when she and Dororo escaped. Although she is a kind person, but losing her son when her husband, Kagemitsu Daigo simply abandoned him causing Nui to be miserable even though she bore another son, Tahomaru. Nui was simply abused by her husband for 16 years ever since he abandoned Hyakkimaru only for learning he is alive. In epsiode 22, She abandoned her status and betrayed her land as well divorced her marriage connection with Daigo to sided with Hyakkimaru and Dororo. However, after Asura's defeat, she died with Tahomaru from the collapse of the land's domain.
She is a tall woman and bears a resemble to her eldest son, Hyakkimaru. She has a long black hair and brown eyes. Like her son, she has thin eyebrows.
She worn a pink kimono with a yellow sash and a green flower-patterned robe.
Unlike her husband who is her opposite, Nui is kind and benevolent who look up to her people and despise violence. She worships the goddess of mercy. She cares the most of all is none other than her missing eldest son, Hyakkimaru. She searched for her son 16 years ago but never found and forced to return to domain. After learning her son is alive, she felt relieved.
However, forcing to abandon their eldest son by his father's orders and suffered by her husband's cruelty, she looks doubtful, shameful, regretful and miserable. Despite of having another son, Tahomaru, she simply ignores his attentions due to her focus on her eldest son, Hyakkimaru. She also disallowed Tahomaru to do as he pleased even if its her husband's orders. She shown little to no care for Tahomaru but wasn't cruel to him. After she stabbed herself, she shown no love for Tahomaru only shown her love to Hyakkimaru. In Episode 22, She betrayed her family and land to sided with Hyakkimaru and Dororo.
She seems to resent her now ex-husband, Daigo Kagemitsu for his selfishness goals by forcing to abandon Hyakkimaru to regain his body by killing the demons regain his missing body parts from them for him of ruling the entire land as the great lord by savaging innocent lives. She suffered from her ex-husband's cruelty as Hyakkimaru suffered as she is meant nothing to Kagemitsu. as Kagemitsu attempting to kill Hyakkimaru, Nui seemly betrayed Kagemitsu after revealed the truth to Hyakkimaru. With this betrayal, their married ties has been divorced and they are not family anymore. In 1969, she sacrificed her own life to protect Hyakkimaru letting the latter kill Kagemitsu to avenge her death.
Nui has a deepest love for her eldest son, Hyakkimaru and considered him as her only true family. She address him as my boy (1969)/son (2019) (坊や, Bōya). She doesn't cares about Hyakkimaru being deformed and always loves him forever making her love for Hyakkimaru too strong that no one can break this love between mother and son even though Kagemitsu tries to make her break it by abusing her mentally.
She seems to have no longer affections for Kagemitsu Daigo and Tahomaru for their failed attempt to kill Hyakkimaru.
She is suicidal by stabbing herself as a sacrifice for the demons before revealed to her eldest son, Hyakkimaru of his father's true nature of sacrificing his body parts for the demons and she show her true love and forgiveness toward her beloved son.
- The Daigo clan has some similarity as the Mishima clan as the family is a curse:
- As Kagemitsu is greedy as Heihachi Mishima. Nui No Kata has similarity of Jun Kazama.
- In 2019, Due to helping Dororo, Nui is considered the best hero's mother.