02/13/2012 02:31 pm ET

Rihanna And Gwyneth Paltrow Flash Some Skin (PHOTO)

Rihanna sang with Coldplay on stage at the Grammy Awards, but it was Chris Martin's wife, Gwyneth Paltrow, whom she hung out with backstage.

Both ladies went for a daring look, showing some skin in sexy side-baring dresses, and Paltrow uploaded a photo to her WhoSay account, tweeting at Rihanna "Say whaaat?"

According to Us Weekly, Rihanna, 23, co-designed her dress with Giorgio Armani, and requested something similar to what Michelle Pfeiffer wore in the movie "Scarface."

Rihanna sat next to pal Katy Perry at Sunday night's awards and continued to celebrate at the after-party.

After the awards, Foo Fighters singer Dave Grohl tweeted, "smokin a doobie at the folkways records afterparty with rihanna and dave grohl #nirhana #Rivana"


The Grammy Awards


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