@Eva M here’s a few ideas:
Female Mime – I bet you won’t have an issue running into another one at the party and you would look completely adorable.
http://www.spirithalloween.com/product/la-mime-jumpsuit-small-medium/
Dreamy Genie – Come on, who wouldn’t love it.
http://www.yandy.com/Infinite-Wishes-Genie-Costume.php
Lustful Pirate – There are an infinite number of styles for this one.
http://www.yandy.com/Vixon-Pirate-Wench.php
Sinful Devil – If they’re on the highway to hell, it might as well be with you.
http://www.yandy.com/Deluxe-Delightfully-Devilicious-Costume.php
Hope that gives you some good ideas!