Song Jian and Su Yun grew up as childhood sweethearts. They are both single-parent families. Uncle Song is a drug police officer and Mother Su is a doctor. They are both busy. Who has time to live downstairs and who has time to take care of the two children? Su Yun is first in liberal arts and Song Jian is first in science. They are the legendary children of other people. Their classmates think that the two are like the happy enemies in the movie Born to Be a Couple. They look down on each other. They competed with each other, and the turning point was when Su Yun discovered that she began to have a crush on Song Jian during college. After a series of stories happened, the two finally confirmed their relationship. When they returned home, they found that Su's mother and Uncle Song announced their marriage in front of them. When Su Yun found out, she quarreled with Su's mother and ran away from home. As a result, Su's mother and Uncle Song were killed that night, triggering a series of events.
