I've watched no more than three episodes of Seinfeld, but I know without a doubt that Elaine is the most hated of the four mains (and the only female). Peggy has the same distinction in King of the Hill. If you had to pick a dozen or so main characters, she'd probably be the only female and easily the least liked. Lisa probably shares a similar distinction in The Simpsons. I have a feeling the most hated lead in Friends is one of the three females, although I've never seen that show. You can probably pull so many more examples.
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