Why in the Middle Ages demons were painted with faces between their legs
It is hardly worth reminding anyone that art is symbolic. But it's worth considering that medieval art was even more symbolic than modern art. Then the artist faced a difficult task to reach the viewer with his work, usually illiterate and not accustomed to indulge in reflection. To get into the idea of the picture, I had to go to various tricks, for example, to draw Satan and devils with faces instead of genitals.
It's hard to say who first came up with the idea of drawing devils with faces between their legs. Such images were created throughout the Middle Ages, up to the 18th century. Plots in which evil spirits tormented sinners were very popular in church books and paintings of cathedrals. The flock needed to be shown the terrible consequences of sinful acts, among which fornication was not the last place.
To depict genitals, even for the most edifying purposes, in theological books and on the ceiling of cathedrals would be bad form, so symbolism came to the rescue. Devouring sinners with a crotch, the devil perfectly illustrated the punishment for carnal sin and the darkest tramp did not need to explain what this symbol meant.
There were a great many options for "humanizing" the perineum of evil spirits. Most often, the painters depicted a monstrous grinning face with sharp fangs and staring eyes. Sometimes the monster's mouth spewed flames, which often took an ambiguous phallic form.
Less often, the masters of the brush depicted Satan with a penis, at the tip of which was the monster's muzzle. Obviously, the extent to which the artist could give free rein to his imagination depended on the customer, whose role was usually played by the church. But, whatever it was, the evil of gratuitous sexual temptation such symbols demonstrated very clearly.
It should be said here that the symbolism was obvious, but hardly effective. Maybe images of Satan and devils with faces instead of genitals were able to impress a young nun or a pious wife of some shopkeeper, but in general they did not frighten the people. Otherwise, how can we explain the fact that in second place in popularity, after illustrations on religious topics, ordinary people had images of a pornographic nature.
The clergy, especially the popes, were not too afraid of being punished for their sins. Among them there were many selected sinners who were not afraid not only of painted devils, but also of real ones.