What makes Emily a mystery in "A Rose for Emily"?

Specifically, Faulkner keeps Emily a mystery in "A Rose for Emily" by using the narrative point of view of the townspeople.  The narrator reveals only what the townspeople know.  Emily is secretive, so the townspeople know little about her.  Only those events that are in some way public are, of course, known by the public. 

The reader knows about Emily trying to keep her father's body after he dies, because the townspeople knew the father, knew that he died, and had to go into her house to retrieve the body.  The same is true for everything else the reader learns about Emily. 

Emily's a mystery to the town, so she's a mystery to the reader.

Emily is a mystery because she lives in such a bizarre way and stays so aloof from everyone else in the town.  Because of this, no one has any idea as to what is going on in her house, let alone in her head.

As far as we can tell, the only person Emily ever speaks too willingly is her servant, Tobe.  When the town fathers come to talk to her about her taxes, she makes it clear she has no desire to really talk to them and they are soon sent on their way.

In addition to the fact that she doesn't talk to anyone, there is the fact of the bad smell that came from her house.  No one has any idea as to why that happened or what was causing it.

So when you add weird things like the smell to the fact that she won't talk to anyone, Miss Emily becomes quite a mystery.

What elements make Emily in "A Rose for Emily" mysterious?

Examples of the mystery surrounding Miss Emily Grierson in the short story, "A Rose for Emily."

• Her age is a mystery. The reader is only given a general idea (probably around 70 at the time of her death).
• Emily is rarely seen outside her house, especially during the last 10 years of her life.
• The reader is left to wonder about whatever happened to Homer Barron (until the end, at least).
• Why did Homer and Miss Emily never marry?
• Why did she refuse to bury her father, allowing him to remain in the house for days after his death?
• What went on inside the curtained windows of her house?

Additionally, Emily's description as a "vision of the past", and her house as a "monument" of the Old South give the reader a sensation of nostalgia and loss which added up to her persona of mystery. We only get tidbits of information about her family, such as the fact that her father was authoritarian and controlled her life, and that her boyfriend, Homer, was disliked. We also wonder about that. How come she ended up with Homer? What inner fascination did Emily have with a man of that class? It is what we know that gives her that air of mystery, but what we do not know is left to a lot of scary thoughts.