The only known Caravaggio ceiling painting, it spans a small room (approximately 30 square feet) in Villa Aurora in Rome. The mural represents three gods, -- Jupiter with his eagle, Neptune with his seahorse, and Pluto with his three-headed dog Cerberus -- gathered around a translucent sphere.
It was commissioned by cardinal Francesco Maria Del Monte in 1597, who used the room as an alchemical laboratory.
It's an astonishing work of art in many ways, but there's one detail that stands out to the queer viewer. Pluto has a healthy patch of pubic hair above his dick. Which is to say, he has a "dick," not a "penis." And seen from below it's almost as if the viewer is on his knees looking up at it.
Maybe not surprising that Caravaggio represents Pluto, god of the underworld, with genitals exposed.