A Pennsylvania man, John Bednarik II, was arrested last week and charged with secretly videotaping a co-worker while she pumped breast milk in her office. Even more disturbing? There have been a smattering of similar arrests around the world. What's behind this blatant invasion of privacy? Here, a brief guide to this creepy practice:

What happened in the latest case?
A woman who works at DeSales University in Center Valley, Pa., had taken off her shirt in her office, and was using her breast pump when she heard a noise. She looked up, and saw a hole in a ceiling tile directly above her desk, partially concealing what looked like a camera lens. She quickly got dressed and walked out, where she bumped into Bednarik as he emerged from an adjacent office. Police filed misdemeanor charges, saying he invaded his co-worker's privacy "for the purpose of his own sexual arousal and gratification." The university has fired Bednarik, who served as its Director of Campus Environment.

Do a lot of men get their kicks that way?
At least two cases eerily similar to the one in Pennsylvania have been documented. In Taiwan, a counseling teacher — who was on a school committee to promote gender equality and prevent sexual harassment — was recently arrested for allegedly planting a spy-cam in a nursing room, and filming five colleagues pumping breast milk. In 2009, a Michigan man, Gregory Mannino, was sentenced to two years' probation and 150 hours of community service after he was convicted of secretly videotaping one of his co-workers pumping breast milk.

Is this becoming a trend?
No, "it would be a little sensationalist to say that this is a 'trend,'" says Erin Gloria Ryan at Jezebel. We're talking about a few cases, although one is enough to make you sick. "What possible appeal could watching a woman pull her boob out and attach it to a machine hold for men?" Not to be alarmist, says Shawna Cohen at Mommyish, but this is an actual fetish. "It even has a name — lactophilia (aka 'erotic lactation' or 'milk fetishism')." And, of course, we're only hearing about the creeps who get caught.

Sources: Daily Chilli, Jezebel, Mommyish, New York Daily News