HP Fans- Who should I dress up as for the Harry Potter Book 7 Midnight Party?

Question:

HP Fans- Who should I dress up as for the Harry Potter Book 7 Midnight Party?

I was going to be Marietta Edgecomb but besides the Pimple Message on her face I don't think anyone would really get it. I want to be someone original, not Hermione, Ginny, etc. I can't be Luna, as my sister (who's going with me) is going as her, and I can't be Trelawney because I was her for the Book 6 Premiere (I won the costume contest xD).
And yes, I still do this stuff.

Best Answer - Chosen by Asker: What about Bellatrix? Or if you are a blonde, go as Narcissa.

If you don't want to go evil, buy a pink wig (or be daring and dye your hair pink for the evening) and go as Tonks!