first - I like that dress!! I love steampunk style clothes. There's some great steampunk stuff on pyramidcollection.com too...
second - there are some very comfortable strapless bras, or you could try a convertable bra and play around with the straps to see if it would work.
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Dance like no one is watching. Sing like no one is listening. Love like you've never been hurt and live like it's heaven on Earth. -Mark Twain
If life gives you lemons, make grape juice, sit back and watch the world wonder how you did it.