Well, my participation in 'Japanese public culture' is now limited to occasional readings of some of the newspapers + periodicals that the OSU libraries subscribe to (plus what I hear from my parents and friends), but I've never read/heard of 'shoujo' and 'prostitution' being used 'synonymously' in it.
That said, 'shoujo [girl]' has been a sexualized figure, probably ever since the invention of 'childhood' & 'adolescence,' in that the idea of innocence has been invested in it (and also in the figure of 'shonen [boy]'), and as you know, pornographic imagination always chaperons the debut of 'innocence.'
Beyond that, schoolgirl uniforms are fetish objects for some men (probably from the time when they were invented). The eroticization of uniforms (e.g. of nuns, nurses, policemen, Nazis, etc.) is so commonplace as not to require much commentary. Uniforms signal prohibition, repression, sublimation, and other rules of power & subordination, while they are also signs of theatricality. Little wonder that sex industries (including some forms of 'journalism') should cash in on it.
The idealization/fetishization of 'shoujo' + 'shonen' may also be a sign of misogyny, if it is accompanied by the disgust felt toward 'fat.' (E.g. Nabokov's _Lolita_.) The only perfect bodies under late capitalism are those of teenagers, male or female. (Does this in part explain the popularity of Buffy?)
On a somewhat positive note, 'shoujo' + 'shonen,' when used by girls themselves, may be figures of resistance--resistance toward gender-defined roles hemmed in by Work and Home.
>titillation as journalism
That's the only way that 'Westerners' + native informants deal with the Orient, or so says Edward Said. Remember, grass is always greener (or lusher) 'on the other side.'
>b) in a recent book on the Takarazuka, Jennifer Robertson claims shoujo is
>(almost) a separate gender from man and woman, what do you think?
I only read a review of her book, so I don't have much to go on here. I'm sure she does a competent reading of resistance/containment (or grammar/excess) drama in the Takarazuka mode of gender/race cross-dressing + fans' 'appropriation' of it all. Here again is a problem of the banality of cultural studies. Once you read Janice Radway, Angela McRobbie, Henry Jenkins, Constance Penley, etc., you've read them all.
Yoshie