I remember the first time I went to a clothing-optional beach in Northern Germany (near the Danish border). I walked up to where there was a drop-off to the beach and looked down, about twelve feet down and away right in front of me, there was a completely naked woman, very pretty and very nicely curved, lying there taking in the sunshine. Complete frontal nudity --her legs were even slightly spread-- and I was fifteen years old, fresh from (relatively prudish) America... Her eyes were closed, and I stood there, soaking in the view. Then - well, you get the idea. Oh, my God, do I remember that!
Now, several decades later, I'd probably yawn, divert my gaze out of politeness, and just carry on up the beach. Been there, done that, it doesn't mean anything (much)... In fact, after some months of living there, with naked pictures all over magazine covers on the newsstands, topless women in ads inside them, naked spas and beaches, etc... I think I was already getting a bit "jaded" to it.
At the other extreme, a woman showing her hair uncovered, or wearing shorts that show her calves, is seen as a completely wanton prostitute begging for sexual assault, in parts of Pakistan. You simply do NOT see female flesh there, to any real extent. The result is that men over-react (by standards elsewhere) to the slightest degree of nudity, or even the suggestion of it. I traveled there a few times with female colleagues (especially one tall blonde one) and the behavior of even waiters in the major hotels, was at times ridiculous, like something out of a comedy movie. They couldn't really help themselves. When you tell them that in some hot climates, women regularly wear shorts and halter tops, they think you are describing either a dream paradise, or a modern-day Sodom or Gomorrah .
In most hunter-gatherer societies, women's breasts are routinely exposed, and are not considered erotic. In Japan, the nape of the neck is considered particularly arousing, when it is exposed. It's all what you're used to, and what the "norm" is in your particular culture.
