The mother of Zhang Wuji, the leader of the Demon Sect, in "Eternal Dragon Slayer".

Zhang Wuji's mother is Yin Susu in Jin Yong's novel "Eternal Dragon Slayer".

Yin Susu is the daughter of Yin Tianzheng, the white-browed eagle king. After Yin Tianzheng founded the Sky Hawk, Yin Susu led the Sky Hawk into the battle for the sword. In order to win the Dragon Slaughter Road, Yin Susu injured Jade with hidden weapons, and then entrusted the escort agency to send Jade back to Wudang Mountain, but was ambushed by a mysterious man, resulting in a broken hand and foot and a lifelong disability.

On the orders of the master, the Five Heroes of Wudang went down the mountain to trace the murder and get to know Yin Susu. They all went to the Yang Daohui of Wang Panshan Tian Hawks, but because Xie Xun, the Golden Lion King, robbed the Dragon Slayer, he was shocked to death by the roar of a lion and forcibly took away Zhang Cuishan and Yansusu. The three of them arrived at Binghuo Island.

Yin Susu and Zhang Cuishan got married on the island of ice and fire, and gave birth to their son Zhang Wuji. And Zhang Cuishan was tied up with Xie Xun in Jin Lan.

Ten years later, on Zhang Sanfeng's centenary birthday, Yin Susu accompanied her husband Zhang Cuishan back to the Central Plains to celebrate his birthday. Wulin people came to ask about the whereabouts of Xie Xun, the Dragon Slayer, but Zhang Cuishan Yin Susu and his wife refused to disclose it. At the same time, Yin Susu's injury to the old things that indirectly led to his lifelong disability was revealed. Zhang Cuishan died of shame, and Yin Susu committed suicide.