do u know??? see here

In ancient England, people could not have sex without consent from the King.
在古老的英国,如果没有国王的同意是不可以有性行为的.
When people wanted to have a child, they had to solicit a permission to the monarchy, in turn they would supply plaque to hang on their door when they had sexual relations.
当人们要生儿育女,他们必须要向君王取得许可,取得许可后,他们会获得一块板,是在性行为时挂在门上的.
The plaque read… “Fornication Under Consent of the King”( F.U.C.K)
那一块板上面写的是…”在国王同意下可以进行性行为”( F.U.C.K)
This the origin of the word