Well, there's no groom Prince StrongHeart, but considering it's from the Flower Ball series I think it's more like a ballgown deluxe kind of dress.

Like in medieval times a ball would consist of several days, as in the original Cinderella story, where each night she wears a dress that's more splendid than the night before.

So this would be something LLL could wear on the last day of the ball. ^^