In short, it's just the love, hate, and resentment of rich people. Studying abroad and cynicism are justifiable for them.
It's not clear whether a girl is chasing a boy or a boy is chasing a girl. Shao Mu fell in love with the other party first, but the ambiguity got to the point where she didn't know if the other party liked her. Due to the possibility of being rejected if she confessed, no one broke the last layer of paper, and because of various reasons, they missed each other when they were young. They had many regrets in their youth, and even more things they couldn't say.
It's a bit silly and a bit cliched.
Purpose: campus love