You don’t hear about this one much, and I wonder why not. Frottage or frotteurism involves rubbing against a nonconsensual person in a discrete, hopefully unnoticeable was to achieve sexual arousal or orgasm. Frotteurs like to work in crowded, public places—trains during rush hour, crowds, concerts. It’s sexual assault and so it’s no joke, and yet I’m surprised you don’t hear about it more.

A girl I know told me about a time she was riding the El during rush hour, holding onto the handle on the back of a seat, being aware that the strap-hanging businessman standing there reading the paper was subtly pressing his groin against the back of her hand. Or was he? It was an awkward moment. If she moved her hand, she’d be admitting that it was happening and embarrass them both. If she didn’t, who knows what she might be a party to? Might the guy actually come in his pants from touching her?

It’s not just men either. Another girl who had a crush on a guy in her office used to dawdle at the elevators at closing time, waiting for her target to get on. Then she’d crowd aboard with him and work her way close enough so she could innocently press her substantial chest against his arm or back. Apparently it worked, and they ended up dating for quite a while. I don’t know if he ever knew of her gambit or if he just found himself thinking of her a lot.

We’re quite aware of the space around our bodies and try to maintain a buffer zone, but modern life throws us into intimate contact with people more often than we’d like. It might be totally innocent when someone presses against you, but since I’ve heard of frottage, I tend to wonder.