What is it about the martyr Saint Sebastian? He has perhaps been represented in art more than any other minor saint, young, lank and handsome, usually naked except for a loincloth, always with a benign and dreamy visage. Sometimes is is shown pierced by one arrow, often near the groin; sometimes he is as prickly with shafts as a porcupine.
I suppose my description hints at an answer: perhaps he is a homoerotic icon, an irresistible subject for artists with homoerotic inclinations. A Google image search would seem to confirm this interpretation.
But maybe that's too simplistic. Straight folks too are apparently drawn to these images, both men and women. Maybe it is the juxtaposition of nudity and mild violence, all those arrow shafts with hardly a drop of blood. "Prick me, stick me, just don't kill me." Whatever is going on, it's got something to do with bare flesh and penetration. Time to call in the psychologists.
For myself, I prefer a subset of the Sebastian theme: The wounded Sebastian tended by Saint Irene, a Roman widow. Here, for example is the representation by Georges de la Tour, suffused with light and tenderness, the candle and the arrow, the hand on the knee, blessedly humane and intensely erotic at the same time. Surely there's a love story here about to develop.
Oh, wait. There is a love story. It's called Valentine (another early Christian martyr who may or may not have existed). And at my suggestion the jacket art of the novel is another representation of Sebastian and Irene, by Hendrick Ter Brugghen, equally tender and and sexy.
Maybe I'm revealing too much of my personal psychoses, but I think it is rather more universal. After all, doesn't Cupid always carry a quiver full of arrows. And think of Bernini's Saint Teresa. Sebastian in Bugghen's painting is pierced through the heart. Irene touches a less fatal arrow as if it were the bow of a violin, as if she were playing on his heartstrings. Look at the composition of the painting: X marks the spot, and the spot is Sebastian's heart, wounded with eros and longing, dead center.