On her 16th birthday, Maizi met Xia Tian for the first time; in the summer of 16, Maizi met Jiang Sijie; in the summer of 17, Maizi gave Xia Tian a notebook; in the summer of 18, Maizi said goodbye to Xia Tian; in the summer of 19, Maizi had been with Jiang Sijie for a long time; at the end of the summer of 20, Maizi became a person again...