There is no line! This is a false line.

it doesn't matter where your body is, in what country it just happens to be moving around in ,or what your body is doing at the time. Its never okay for someone to be touching any part of it without your consent.

He can lie and say its the culture but I know of no culture in which it is okay to be grabbing up on a woman who is a stranger, a tourist or who is under 18.