Southern Gothic authors like Faulkner, Tennessee Williams, Flannery O'Conner, Harper Lee, Eudora Welty, and others focused the Gothic horror in some of their stories on the way a strict society can hide inner psychological horrors. "A Rose for Emily" fits this characterization perfectly.
Decay is a major motif in Gothic and Southern Gothic writing movements and images of it – both literal and figurative – litter the prose of the story, encompassing the setting and the social mores of the Southern town of Jefferson. Miss Emily's house itself is a symbol of decay, literally, at the end of the story, when the upper floor has been abandoned and has an actual dead body in it. It is also a symbol of figurative decay, as it represents the lost way of life of the antebellum South. It is described as:
"a big, squarish frame house that had once been white, decorated with cupolas and spires and scrolled balconies in the heavily lightsome style of the seventies, set on what had once been our most select street."
Though the house sounds beautiful and ornate, the area around it has fallen to northern industry and progress and it now sits "lifting its stubborn and coquettish decay above the cotton wagons and the gasoline pumps--an eyesore among eyesores."
Like the house itself, the society that Miss Emily and several older Confederates still subscribe to is in a state of decay. Emily is born at the end of the Civil War, and so the trajectory of her life encompasses huge changes in Jefferson and the South as a whole. Some of the older folks and the aristocratic families cling to their values: Emily's father's Grierson pride keeps him from accepting any suitors as good enough to marry Emily, while chivalrous gentlemen like Colonel Sartrois and Judge Stevens see her as a damsel and remit her from taxes and refuse to confront her about the smell after her father's death. As the years go by, though, these attitudes and behaviors die out, making Miss Emily a decaying relic of a dying culture.
The setting of the story also relates to the theme of anti-social behavior and isolation that so interested the Southern Gothic writers. Miss Emily is a mysterious figure in the town. When the narrator speaks of the present, no one talks with or visits her and she's even given up giving her china painting lessons. When she dies, mourners come "mostly out of curiosity to see the inside of her house, which no one save an old man-servant--a combined gardener and cook--had seen in at least ten years." When Jefferson begins getting the post mail system, Miss Emily refuses to affix the metal numbers to her house – she is literally off the grid. Setting up Miss Emily and her house as isolated and mysterious makes it clear that she is hiding her twisted psyche – shown by the fact that the townspeople aren't surprised to see the decaying body of Homer Barron in a room on the top floor.