In this tweet, a woman recounts how she had to endure an entire metro ride in Mexico City with a man touching her from behind, with an “it-wasn’t-me” look on his face. She was 12.

Another woman recalled how, when she was 13, her aquatic ski instructor thought that it was necessary “to touch me and put his penis near me” for her to learn to ski.

The bullying continues past puberty. Several women posted that they couldn’t recall the first instance they had been harassed, since it had happened so many times. The list of incidents is as long as it is infuriating. Men ejaculating on women in public transit, or using their bodies to masturbate at open-air events.  There’s flashing, obscene comments and gestures, and slapping women’s behinds as they walk on the street.

Some men have used the hashtag to show sympathy or to apologize for improper behavior. One man said on Facebook that it never occurred to him that touching his sisters’ friends or lifting their skirts might be scary for them. He knows better now, based on his post.

But others used social media to continue harassing women. “How interesting that those who feel offended by catcalls are the type of women to whom one would never say anything flirtatious. How interesting that almost all feminazis are fat and ugly,” one of them posted.

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