Esmerelle

Background
Bann Esmerelle is the most important figure within the nobility of the Amaranthine area; by far the wealthiest and most powerful, and ultimately the bann of the city of Amaranthine. She was known as being a supporter of Arl Howe, but she is too powerful to be ignored or displaced.

Involved In
Bann Esmerelle appears when you first meet the nobles, as one of the two most important nobles Seneschal Varel says you must speak to - the other being Lord Eddelbrek. The two nobles compete for placement of troops; Esmerelle wants to keep troops inside the city, and Eddelbrek wants patrols for the farmlands.

Esmerelle is later found to be the head of A Brewing Conspiracy, to displace the Wardens.

Result
If the Conspiracy is left to run it's course, Esmerelle will attack you with her conspirators. Her death is covered up, as is mentioned in the epilogue

If the Dark Wolf is hired to deal with the Conspiracy, Esmerelle will not be found with the conspirators, but will hang herself in the epilogue.