This is a good 'how to' on a lingerie cake, uses box mix. I would stick with simpler icing design though. You could use those pearl looking sprinkles to decorate with! Or roll out the pre-made fondant if you're feeling really adventurous.
Lingerie Cake...EEEK I have this cake mold Ash!
Custom Decorated Corset Cookie for Bridal Showers, Lingerie or Bachelorette Parties