I have written a few edgy short stories, and I enjoy reading them. As an example, Hilary Mantel’s story of Margaret Thatcher’s fictional death
It’s the suggestion of outrageous possibility that can make a story or an image edgy.
If the first person form is used as a literary device, the narrator of an edgy story is often unreliable, but his or her fantasies around true events don’t make a fantasy for the reader. There can be a self-deception that the reader can assess.What is ‘edgy’ is the uncertainty around what is real, especially if that threatens safety, physical or attitudinal.
Where stories are written in the third person, the main character does not have to be likable. It is edgier if s/he’s unlikable yet the reader constructs a sneaky liking for him/her. This makes the reader uneasy. (What sort of person must I be if I feel sympathy for this jerk?)
The author can shock the reader by reversing all expectations, or make the protagonist cross over some unacceptable line. He may kill but must he debase? He may cheat, but the person who has just saved him, or his own mother?
Edginess needn’t involve extreme sexuality or aggression. An action close to home can cause the uneasiest feelings, or an everyday event suddenly appearing to have a different significance. It doesn’t have to involve crime or erotica. It can suggest something subtly sinister. It can be socially provocative. It can even be shockingly funny.
Assumptions we make when we read a story when reversed, can highlight our own prejudices. Edginess can produce unease and give rise to questions over morality, practice, managing relationships. A story is satisfying when it is thought-provoking and lingers in the mind after the last page.