What do you mean by pulling the red line?

Pulling the red line is also called pulling the red line, which means matchmaking.

This statement originated from ancient myths and legends in China, where the old man in charge of marriage would fix the marriage for men and women with red lines.

In ancient times, when a man and a woman got married, the woman was led by the man with a red line (cloth) because a less conspicuous road was covered on her head. Later, it became a wedding ceremony for men and women.

Nowadays, the red line is that the matchmaker brings together two men and women who don't know each other.