Complete the indicated chapter to unlock the corresponding dress.

Classic     - Infernal Train (Chapter 6). 
              When equipped you will regain health when shrunk.
Misstitched - The Dollhouse (Chapter 5). 
              When equipped your Shrink Sense duration is doubled.
Royal Suit  - Queensland (Chapter 4). 
              When equipped your health is limited to four roses total.
Silk Maiden - Oriental Grove (Chapter 3). 
              When equipped your enemies drop twice as many teeth.
Siren       - Deluded Depths (Chapter 2). 
              When equipped your enemies drop twice as many roses.
Steamdress  - Hatter's Domain (Chapter 1). 
              When equipped breakables drop more teeth and roses.