What could i possibly be for halloween with this outfit?

I'm in college so parties start tonight & I have no idea what I want to be! I'm thinking I could wear this black sparkly fitted club dress/shirt. The front is black sequins & the back has the cross back & it looks like a club dress & fits my shape tight & goes to a little bit below my . Since its kind of chilly out & I'm not trying to look skanky I was going to wear black leggings with it that go just below by knees. If someone asks me, what character could I say I am for Halloween? And what might I add to it to look a little more Halloween-y? :) please & thank you