A box for a cello. According to NetEase Cloud Music Query, "Anhe Bridge" is a song sung by folk singer Song Dongye. The "girl holding a box" in the lyrics is Song Dongye's ex-girlfriend. Her ex-girlfriend is a musician who plays the cello. She used to I just came to watch Song Dongye's performance with a cello in my arms. The box was the box that contained the cello, and the "man wiping sweat" was Song Dongye wiping his sweat during the performance.