Beauty is pain!
And well, we mostly mean that literally. Ha!
The sexy supermodel stripped down to just her undies for a racy shot with the designer, sharing the pic on Instagram yesterday.
Though she wrote for the caption:
"@zac_posen ….I need something to wear for tonight's@projectrunway @lifetimetv"
Oh, well it all makes sense now!
[Image via Heidi Klum/Instagram.]