A monogamous person would not have sex with others. Being naked in artwork is different, it doesn't mean others can't see a naked picture of them. Because why not, the Gods aren't prudes who think nudity is a sin. In the ancient times, it was said that even virgins would be naked. In saunas etc, everyone would go naked, of all ages.
There is nothing wrong with nudity, it's how we enter the world, why be scared of skin and genitals when we all have them.
In this society, with everyone on such a low level of consciousness, sex is like "omg a naked person!!!!!!!!" Whereas when you are on a high level of consciousness, it's more like "whatever, we all have bodies and skin". Yes sex is sensual and highly important, but it's not the huge and taboo deal most people here think it is.
The Gods are far above us in every way, so don't expect them to be down on our level. Reach up to them instead.