Sure, your cute dress is a little shredded now, but it still looks great.
You can feel it in your bones. Ever since you were walking on your own in the middle of the midnight forest one month ago and were bitten on the neck by a terrifying, slavering, unseen monster, you've known that you were somehow changed. The night of the full moon is this very night, and it corresponds with Halloween - a doubly potent time of year. When you realized that you were transforming, you were getting dressed for a night out.