Gu Nan has liked Duan Muchen, his neighbor's little brother, since he was a child. He has cared for and doted on Duan Muchen in every possible way.
Later...
Duan Muchen: "Gu Nanyi, thank you for growing up with me!"
Gu Nanyi: "Duan Muchen, thank you too for staying with me until I grow old!"
Intention: As long as people are here, water will always flow, and this feeling will never end!