A friend of mine is an japan right now - he's not fat but not skinny either, I'd guess BMI 21-22 and he told me that they openly call him fat all the time. As a women with a BMI of 19,6 I'd probably be fat too. From what I've heard you are supposed to be at 16-17 as an ideal BMI for young women? Maybe some japanese shitlord/lady can tell us how it really ist :)