As her name implies, she is an eight-hundred-year-old nun. She herself has the kessen-chu and has imparted these blood-worms to both Manji and Shizuma.

Yaobikuni finds Rin Asano at the graveyard where Rin's father is buried. After hearing her story, Yaobikuni urges Rin to find the toughest, strongest yojimbo of all, Manji. Yaobikuni is short in stature and has spiral tattoos on her face.