Sun Erniang is a fierce woman with a vicious and murderous look on her face. She has strong arms and legs that resemble clubs. She is well dressed and uses heavy cosmetics, which make her resemble a yaksha. She is hence nicknamed "Female Yaksha". She is highly skilled in martial arts. Sun Erniang is one of the scout leaders of Liangshan. At last, she is slain by the enemy officer Du Wei at the battle of Qingxi County during the campaign against the rebel leader Fang La.