Lu Yu and Hai Fan met in high school and fell in love with each other secretly. The two ended up in vain due to a small misunderstanding. Many years later, the two met by chance. Lu Yu discovered that Hai Fan had changed from an innocent and carefree stupid girl to a calm and introverted adult. He also discovered that Hai Fan suffered from depression, so he accompanied Hai Fan to gradually recover. Haifan finally plucked up the courage to mention that little incident back then to Lu Yu, and Haifan untied his knot...
Concept: A very small misunderstanding in childhood triggers some regrets in youth, and even becomes an unsolvable knot in adulthood. However, there are only two people in the world who can untie the knot, one is the other person, and the other is you. No matter how hard the knot is, no matter how long it takes, don't give up on untying it.