Groping, being molested by strangers in a packed car/carriage? I presume it must, during rush hours on certain train lines there are sections dedicated for female passengers only. I mean in a place where passengers require the assistance of station employees to help push everyone in side the care until the doors close, once you're stuffed in there you can't even move at all if someone tries to take advantage of you.
Its in a lot of manga's and manhwa's, even the ones that arent yaoi. So this really happens???