Unfortunately, at least in America, a woman's right to express her sexuality , at least in the way the media portrays it, overrides her right to be intelligent, her right to be independent, her right to be strong, her right to be her own person, etc, especially considering the long history in the west of women being nothing more than a sexual beings. This has a lot to do with why I, as a woman, am sensitive to other women expressing themselves in ways that could possibly objectify themselves (I know that is their right, but it is also my right to disagree with them).
As for what kind of sexuality attracts certain, seedy types of men, I think it has more to do with acting without repercussions than anything. Take ads in Japan for the game "Bayonetta", where passers by were encouraged to pull flyers off a wall, revealing a giant image of a naked woman (the title character). It encourages that type of control that allows one to act without any consequences
Luckily, that's not what Ayu is about, and, while I'm sensitive a specific part of her image, it's nice that she is so well-rounded, and what I dislike is only a part. It also makes a big difference that, as other members have pointed out, this shoot is for a women's magazine. It's still not my favorite photo (for other reasons, too, like the extremely heavy eyeliner), but at least it's not in a men's magazine.
(For the record, I'm just expressing my opinion. I'm not Ayu-bashing, or putting her down or calling her a w**** or bashing or putting down anybody else for that matter, and I hope it doesn't come off that way). I'm glad we have a forum where we can express our individual views on different topics.)