one time I was listening to Maddy in the morning (a Boston morning talk show) and they pranked die hard Red Sox fans to read a script that said something like "my name in blank, I live in blank and I love the Red sox. But the Yankees aren't that bad either, and A Rod is a nice guy" and they said it before they realized what they were reading and they were PISSED so the person who pranked them was like jeez you really hate the Yankees don't you and one guy goes "If I was in a room with Hitler, Stalin and A rod and had a gun with two bullets I would shoot A Rod twice" and I was crying laughing because then the guy had to apologize the next day on the radio for comparing A Rod to two of the worlds worst people.
Workplace? I'd report her to HR. Reguardless of context, that's a threat of workplace violence. If she hates me that much, I don't want her working where I do, much less with her directly.
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School? Even worse... that would end up on the news.
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School? Even worse... that would end up on the news.