This isn't a new dating trend. But it's got a name now. "Roaching" is the new term for when you find out someone's cheating on you with a TON of other people.
Cheating with one or two people doesn't count. It has to be more than that. So they're a serial cheater who's been seeing a bunch of other people behind your back.
It's called "roaching" because of that gross feeling you get when you turn on the lights in a room and see roaches scatter. So the people they're cheating with are the "roaches," not the person you're dating. Which seems a little unfair