Li was born in Wuhan, Hubei province. Her father, a former provincial badminton team player, wanted his daughter to be a national champion. So Li started badminton training at 5 years old, before turning her hand to tennis at age 8.

Li would go on to far exceed her father's expectations. "But back then, her father only knew that his girl was gifted. What he did was to try to find ways to inspire and nourish the youngster with all he had," A Jia says.

Her father died of a congenital vascular disease at the age of 39, when Li was just 14. One year after that, Li would claim her first national singles championship.

Their last meeting took place at a railway station in Wuhan, where, during her trip to Shenzhen from Beijing to attend a tournament, Li enjoyed a brief encounter with her ailing father on the platform for just several minutes. Li didn't know the severity of her dad's situation, and he promised her that he would soon be back on the sidelines cheering her on.

"In the picture book, the father is depicted as fading into transparency as the train pulls away and he waves Li off," A Jia says, "which is heartbreaking and poetic."

He says that, as a father, it is his favorite scene.