There are clear signs from the picturer that the female figure portrayed is meant to be as beautiful and erotically desirable as the Venus sculpture it mimics.
The facial type of Sebastiano's Saint Agatha was in vogue in Rome at the time. It is the probable representation of a contemporary woman in the guise of a saint, presented semi-naked in the pose of a fragment of a classical sculpture of Venus
It is clearly documented that at this time there was a problem calling up lascivious rather than pious desire in the viewer through images of beautiful saints.
It was against paintings such as these that the reformers in the Council of Trent railed and acted against. In 1563, the Council of Trent ruled that in religious images, "figures shall not be painted or adorned with a beauty exciting to lust."
The reformers were not exercising a prudish dislike of nudity, but were consciously rejecting a new genre of image, one that deliberately, and intentionally, exploited equivocal--and sometimes contradictory--social notions about flesh, sexuality, and spirituality.
I wonder also about the "story" or "narrative" itself. What do we make of the spurned guy? And does Agatha's eventual achievement of sainthood diminish his jerk status? I don't think so...