紅線

Noun

 * 1)  red line; red string
 * , relationship between a predestined love couple ; marriage or matchmaking
 * 1)  betrothal gifts
 * 2)  central and politically correct theme of a piece of writing
 * 3)  main thread in literary works
 * 4)  red line a boundary or limit which should not be crossed; bottom line

Proper noun

 * 1) Hong Xian, the protagonist in the  tale