The daughter of Ji Ning and Yu Wei. Yu Wei decided she wanted to give a child to her dao-companion, Ji Ning, after the Seamless Gate tried to use her to assassinate Ji Ning.
Ji Brightmoon was born during the chaos of the Crimsonbright Realmwar, just days before her mother's death by suicide. Her mother's death affected her greatly making her much more attached to her father, Ji Ning.
Ji Brightmoon was able to talk immediately after being born, and was born the size of a three-year-old child. She had a divine tattoo of a flame on her forehead, and she was surrounded by flames "as though she was a young fire elemental." She was also born with a Zifu-level Fiendgod body with innate control over and affinity with fire.
Ji Ning and Yu Wei named her Brightmoon after the "Brightmoon Diagram of the Mountains and Rivers that he and Yu Wei had grown close and become Dao-companions (inside of)" during the Conclave of Immortal Destiny.
Throughout the story after her birth, she seems to retain her youthful charm and innocence, as well as her attachment to her father Ji Ning. She does not share her father's obsession with cultivation and seems to like just enjoying her life and occasionally pranking others. However, she does seem to spend much of her time with her father, and later with her grandparents after Ji Ning revives them.
She is currently a Daolord of the fourth step.