This is an upgrade of Nelly Johnsons Little Black Dress. We're talking a Bureaucrat only item. Even so, when this piece was introduced, most of population breathed out in relief. Why? Have you ever seen a trox wearing a dress created to seduce?
Nelly's Dress in itself is hard to get, since it drops from Nelly Johnson, one of 5 high level mobs refereed to as Mercs. There is an upgrade item needed which is Nelly's Chip, it drops from a Hollow Island Champion. But luck gives, it drops from the first one, so there's not much force needed.