After Chu Bilan traveled through time, she spent 6 years in an ordinary way, but when it came time to get married, there were many twists and turns. First she was abandoned by her fiancé and then forced to marry by the third prince. Chu Bilan had no choice but to decide to settle her marriage with a contract. At least it was a choice she could make.
God always takes care of people who travel through time, and Chu Bilan is no exception. She met a better man. She thought she might be able to get close to his heart and grow old together with him.
They made a contract for their marriage, which lasted for a lifetime.
PS:
Everyone has secrets in their heart, and Chu Bilan's participation seems to expose all the secrets bit by bit. Good or bad, either deal with it or accept it. Protecting the people around you is the most important thing.