As this is a frequently asked question, here is some background to explain why the leads’ names are funny.
Zhang San
Zhang (张) is the third most common surname in China and it has very ordinary / neutral connotations, like "Smith" or "Johnson".
San (三) is also a very ordinary name. It means "three" and it used to be common for rural families to name their children in order, with the third child being named "三".
Together, Zhang San (张三) has a more specific connotation and usage, like the equivalent of "John Smith" (the go-to example of a very basic, ubiquitous, ordinary name) or "John Doe" (a placeholder name for any person).
Wang Cuihua
Wang (王) is the #1 most common surname in China and is more prevalent in northern China.
Cuihua (翠花) is also a name that used to be very common. It strings together some nice concepts (jade or emerald green - 翠 - and flower - 花), but it is a very literal (i.e., not abstract and elegant) and also strongly associated with country girls (especially country girls from northeastern China / especially in a stereotypical or comedic sense) and a much older generation.
Notably, the FL's third great uncle gave her this rustic, old-fashioned name.
There was a 90s song called "Northeasterners are all Living Lei Fengs" (东北人都是活雷锋) that got very popular in the early 2000s that had a line ("Cuihua, serve pickled cabbage!" / 翠花, 上酸菜!) at the very end that became iconic and can be used as a funny reference for someone to imply that a lady is a bit rustic in a light-hearted, familiar, teasing way.
The song was also used as the theme song for a TV show (A Family in Northeastern China / 东北一家人) in 2001, with the iconic line voiced by one of the main characters of the TV show. One of the characters in the show is a waitress from the countryside named Cuihua.
The line is so well-known that:
- university drama students (including Deng Chao) put on a production of a play that opened with the song and that was titled "翠花, 上酸菜!";
- when an at-home-cabbage-pickling machine was invented in China, the news used the iconic phrase in their headlines for the story; and
- there is a brand of pickled cabbage called "Cuihua Pickled Cabbage" (翠花酸菜) that is produced by Heilongjiang* Cuihua Group (黑龙江翠花集团), which uses a country girl image as a kind of mascot.
*Heilongjiang is the northernmost and easternmost province of China.
There are other Cuihua-related tropes and phrases, but that's the main one that's relevant here.
The ML used that famous line ("Cuihua, serve the pickled cabbage!") when he was laughing at the FL's real name in episode 29.
In a way, it's almost like an early meme that's old enough for him to have known about it before he transmigrated into the historical story in 2016.
Although not an exact equivalent, it's a bit like if their names were "John Doe" and "Mary-Sue Smith".
