Rouputuan, also known as Huiquanbao and Juehouchan, and translated as The Carnal Prayer Mat or The Before Midnight Scholar, is a 17th-century Chinese erotic novel published under a pseudonym but usually attributed to Li Yu. It was written in 1657 and published in 1693 during the Qing dynasty. It is divided into four volumes of five chapters apiece. It was published in Japan in 1705 as Nikufuton with an preface proclaiming it the greatest erotic novel of all time.
The novel had a controversial status in Chinese literature, and has long been banned and censored; recent scholarship treats the work as an allegory which uses its unabashed pornographic nature to attack Confucian puritanism. The prologue comments that sex is healthy when taken as if it were a drug, but not as if it were ordinary food.
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