Facing one's own desires is a difficult thing, and the undercurrent is not only lust, but also struggle and self-loathing. The disunity of inner character and sexual orientation in the movie is very good. The submissive heroine is more frank and firm than the dominating control freak in facing herself honestly.
Secular prejudice against niche orientations (excluding situations of harming others, of course), including the common sense of shame and guilt in the client himself, is often caused by conflating orientation with personality, just as not all gay men are feminine, People who dominating in orientation are also likely to be shy and introverted in life. If we can look at the two separately, we can understand more about them.
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