I think in general, if the girl is naturally cheerful then it will probably show up in the pics...but then some will put on that"kawaii" face when theyre not actually like that.
I think it also matters when the photoshoot is done. Some girls may have them straight after they arrive from mainland, sometimes at night, when they are knackered and can't be arsed, so look slightly disinterested or even pissed off.
Obviously agent pressures play a big part as the girls are probably told to seem like they enjoy it. Some girls who sorta know they look good will probably pose for it but in fact are stuck up and give bad service.
Too many variables I guess. Sometimes I do like those half angry looking ones in the hope that they're wild in bed!
