It means that purity is displayed inside the brothel, and elegance is displayed below the archway. It's a polite way of swearing.
The Book of Songs is divided into three parts: Fengya Ode and Fu Bixing. They all represent elegant art, which can be extended to noble personality, etc.
Goulan was a performance venue for folk arts, dramas, acrobatics, etc. in the Song and Yuan Dynasties. After the Ming Dynasty, brothels were also called Goulan. Goulan Courtyard Fengya Song: It means singing and dancing in a romantic place, that is, pretending to be pure in a brothel.
Huaiqing Terrace was built by Qin Shihuang and is similar to the Chastity Archway. During the reign of the First Emperor of Qin, there was a woman named Qing in Bayi who had been widowed in her early years. She "used her wealth to defend herself against intrusion. The Emperor of Qin considered her a chaste woman and kept her as a guest, so he built a Qing platform to conceive his daughter." Huaiqing Fu Bixing under the stage means to pretend to be elegant under the archway.
For example:
In the drama "Half Honey and Half Injury", Mr. Wan used the sentence "Goulan Courtyard" when describing the male supporting actor Du Lei (played by Gao Hanyu) "Ode to elegance, Huaiqing is full of excitement in the audience."
The implicit meaning of this sentence is to scold Du Lei for being both arrogant and arrogant. He clearly contributed to this incident and even caused the heroine Jiang Jun to be injured. But here he said, "I don't want this to happen again." He is obviously a bad guy, but he still wants to act like a good guy.