I began writing this character in her first year at Hogwarts in a fic titled The Muggleborn Slytherin, but realized that all the bits I wanted to write took place during the war...so I skipped ahead a bit. I've left the first two stories, The Muggleborn Slytherin and Hide and Seek with the Heir of Slytherin as well as the collection of oneshots in "This Grimmauld Place" up for now, in case I have the urge to go back and keep writing or do character development or whatever, but I'll be focusing on my wartime fic, title It Has Begun.

Summary of It Has Begun: The Dark Lord is gaining power, Albus Dumbledore is dead, the Order of the Phoenix is scrambling and the Boy Who Lived is nowhere to be found. But there is still a war to fight.

If you want to look for It Has Begun on AO3, it is also posted there (I like AO3's format a bit better).