Goodbye Sister | K.Mikaelson

Y/n Petrova is ,how do I put this, a complete bad bitch.
Now what if when Klaus killed Katerina's family he did not kill all them he did however, keep or in- slave her sister y/n and had a witch create a fake body to create the illusion that miss y/n Petrova or pierce if you would was dead. But what if she came back to mystic falls but married to klaus and is a witch herself .

Disclaimer: This was my first story. Therefore it isn't very good and lacks description also major holes in the plot. Also very rushed.