This anonymous inscriber lays claim to sexual grafitti as one branch of erotic art.

Graffiti, as we all know, is not always sexual in nature. It is more often sexual when produced by men than when produced by women. Kinsey and his colleagues investigated sexual and non-sexual graffiti (as they appear to have investigated everything else) and documented and tabulated their results. A high proportion (86 per cent) of the inscriptions on the walls of the male toilets were found to be sexual; but not more than 25 per cent of the toilet wall inscriptions made by women dealt with sexual topics (genitals, oral and anal sexual behaviour, "obscene" words, etc.). Most of the female inscriptions referred to love or names were associated ("John and Mary," "Helen and Don"); the drawing of hearts was common in the female toilets. In 331 female inscriptions, there were 69 per cent depicting lips, 35 per cent making non-erotic references to love with the opposite sex, and 12 per cent making non-erotic references to love with own sex. The scores in the other Kinsey categories were considerably less.