This is going to sound fairly strange. I was in an HP game where people from one reality got transported into the bodies of themselves from a different reality. I had a character that was fairly minor in scope in the books that later in life was abused by her Slytherin Death Eater husband. When she was taken to the other world their roles were reversed and she was the snippy angry Death Eater and he was the one that didn't care. I never got to play out the complexity of such a relationship and work out them relearning each other and him finding out how horrible he was in her world.
In short I would love for someone to play one of the older Slytherin students Miles or Terrence, I would even take an original if you so wished or one of the unmarried Death Eaters that never got sent to Azkaban to play against her. Her information is here If you like the idea I would even be willing to some how take the HP elements out of it.