ET's TOP 5: RiRi's Most Scandalous Shots

Anyone who's ever so much as glanced at Rihanna's Instagram knows that the 25-year-old pop star isn't afraid to flash a little skin.

RELATED PICS: Rihanna's Most Jaw-Dropping Photos

From topless to bottomless, this S&M singer has shared (and bared) it all through the years, and now we're counting down her five most scandalous shots.

What do you think of Rihanna's scantily-clad pics: sexy or inappropriate?