Biologically, human cells undergo metabolism. It took seven years to replace all the cells in the body. 21-Year-old Li Su always wonders whether Fu Minghao has become a different person now.
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14-Year-old Li Su left a message on Fu Minghao's space, "You will always be my sun, Brother Fu."
18-Year-old Li Su feels that he is the luckiest person in the world. He has Fu Minghao by his side.
Li Su, 21, feels that he is the unluckiest person in the world.
Concept: painful youth