Koda Kumi has mostly female fans... Even if by western standarts this photoshot is sexy, it's not what most japanese men find attractive at all... There's a reason why most of Morning Musume and AkH48 fanbase are made of older men, and why girls like Ai Otsuka and Aiko always own the "who would you like to date" polls
This is sexy to most japanese men:
And this is the kind of girl people will see on male oriented erotic and pornographic publications and videos... Actually, Ayu was more like this when her covers were "artistic" than now... Most of her sexy shots (and not only Ayu's, but also Koda's and Namie's) are made to show power and control over her own sexuality, pretty much like Madonna do... Not really to attract men (actually, most men have tons of problem dealing with strong and sexual women, not only on Japan, but anywhere in the world)