Ow ow! Rihanna is looking super sexy and semi-naked in her new series of ads for Armani Jeans and Armani Underwear's A/W campaign. The Barbadian singer, who has never been shy about showing some skin, stripped down to her bra and panties for the Armani Underwear ad. She also did a gravity-defying back bend over the hood of a car in a bra, leather jacket and denim for another Armani ad.

In the first ad (shot by Steven Klein), Rihanna looks like she could be a film noir temptress as she seductively sits in a vintage car in nothing except her lacy skivvies. The black and white photograph adds to the alluring quality of the advertisement, but Rihanna's rock-hard body is truly the star of the photo. It's impossible not to look at this picture without some sort of "wow" expression.

The second ad is a little more tame in the sense that Rihanna has more clothes on. However, her open-mouthed, back bend pose absolutely oozes sex as she rests upon the hood of the old-school, jet-black Lincoln Continental.

Harper's BAZAAR has another photo of RiRi posing in her underwear, but this time she has switched out the nude-colored bra and panties for a black lacy set.

The 'S&M' singer also posed for another Armani Jeans ad recently, and we are digging her black on black outfit. We have one question though -- what is up with that bleach blond hair? We aren't feeling the bowl cut look at all, or the color. Is she planning on dressing up as Fred from 'Scooby Doo' for Halloween? If not, we say ditch that do and go back to the red!