Working within those rules, Allie posted something vague about her situation. “Essentially, I wanted to find out how much of an idiot I’d been, so to speak, and whether this person was prolific and endangering other people or not. My main concern at that point was the safety of other women.”

There were a few back and forths with other commenters, but nothing Allie was able to verify. When her partner later gave her the names of all the people he’d slept with, she recognised some of them from the comments – but her activity in the group stopped there. She already had the confirmation she was looking for. “When your reality blows up in your face, it’s very isolating,” she says. “You don’t know whether you’re over or underreacting. I think the group served as a reminder to trust my instincts – the fact that this sort of thing is prolific doesn’t mean you’re crazy, it means the other person is shitty.”

More anonymous corners of the internet, such as Reddit, focus on the ethical questions, such as does sharing people’s dating profiles, private messages and photos without consent count as doxing?

is a big topic on TikTok. Searching the term will bring up everything from videos of British women warning of karma and comeuppance set to a dancehall track, to a US standup joking about posing as a woman in his local group to get an honest review of himself. And how would we feel if the genders were reversed?

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