Sometime after MK defeated the Demon Bull King, the little girl tried to get her cat down. However, when her cat ran away, she was later possessed by Lady Bone Demon. As a result of being possessed, the little girl was used as Lady Bone Demon's vessel and for her deeds.
After MK was about to escape from the Silken Web Cave, Lady Bone Demon used the girl's body to trick MK into thinking that she was a little girl that got lost.
As the Lady Bone Demon used the bone mech to fight MK, the latter attempted to use his powers to destroy it. However, it instead let Lady Bone Demon grow stronger, and changing the little girl's appearance into Lady Bone Demon's true form.
Lady Bone Demon's hostess is a little girl that has long black hair with bangs.
Lady Bone Demon's hostess wears a dark sea green long-sleeved jacket over a white shirt, a pink skirt, and white shoes. She also wears a pink hairband.