Acrobatic Silky was a yokai that had been stalking Aira Shiratori since she was a little girl.

Due to her tragic past of having her child taken from her, Acrobatic Silky was a yokai who had a desperate need to find a child to love and call her "mother." Her main attraction was Aira Shiratori after becoming delusional in thinking that she was her mother during the time she was alive and was obsessed with having her all to herself. Acrobatic Silky's intentions also leaned towards her maternal instincts to protect the one she loves, as she was willing to sacrifice her own aura in order to revive Aira and ripped out her jaw to assure Momo that she would not try to eat her. She also took great pride in her acrobatic skills.

(Source: Dandadan Wiki)