Agnolo Bronzino, Venus, Cupide and the Time (Allegory of Lust), 1540-45
Calls to mind the recent spate of teachers in the US having sex with their students, doesnt it? This blatantly erotic painting was a gift to the French royal house. I tell you, those French kings... These days, this stuff is called child porn. There is indeed a fine line between art and porn and this painting straddles that line.