Su Ziyu is Jiang Wu's adoptive younger sister. She was born 18 years ago and was paralyzed from the neck down after a car accident that killed her parents eight years ago. She can only move her neck and barely her right hand. She is extremely thin and pale, barely alive. Jiang Wu cares for her daily, massaging her limbs and trying to save money for her surgery. She is aware of her condition and tells Jiang Wu not to waste money on her. She is a motivation for Jiang Wu's actions. She survives the initial apocalypse with Jiang Wu's protection and is given antitoxin by him. She is fragile but determined.
