Is there anything left that the world hasn't seen? Rihanna poses in several raunchy photos that were taken and posted by her best friend Melissa Forde.

While posing nude for the cover of GQ and her very own album seems acceptable, Rihanna treats her fans for a free show. In a series of naughty photos posted by Melissa Forde on Instagram, the "Diamonds" singer was photographed wearing nothing but a bra.

In the photo, Rihanna was seen sitting beside a fireplace while only wearing a lacy bra and a hooded fur jacket. She was holding a glass of wine and gazing straight to the camera.

In the two X-rated photos, Rihanna was close to exposing too much for the eyes. Sitting on the floor without her underwear, the 24-year-old singer sips on her glass while Melissa snaps away.

"Sneak peak new photoshoot @rihanna #MTFphotography," Forde captioned together with the photos.

Rihanna's friendship with Melissa started way back before she even became a global phenomenon. During concerts, parties and even holidays, Rihanna is never without Forde.

And while her friend is probably starting a career in photography, Rihanna was more than willing to be the muse. In one photo that Melissa took before, a risqué Rihanna exposed her breasts.

But who's not used of seeing the singer in an "almost naked" state? In her very own Instagram account, Rihanna frequently updates her fans with saucy images of herself.

The world has probably seen everything there is to see and with little left to the imagination of her audience, it won't be long before her fans yawn at Rihanna.

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