Why are perverts called gentlemen?

This is a saying in ACG circles. At first, there was a classic quotation in the animation "Flower Marriage of Seto" called "Although writing a mermaid, it is read as a benevolent person". This style was later widely spoofed, in which "writing a gentleman is read as a pervert" is generally a mockery of those characters in Japanese animation who feel good about themselves but are actually obscene men. The most famous one should be the "Destiny Stone"