This really has nothing to do with 'rather', I think, but has to do with using m-dashes (not hyphens), which are an informal equivalent of parentheses or commas: These males are behind, but this doesn't relieve women – or girls, rather – of their responsibilities. These males are behind, but this doesn't relieve women (or girls, rather) of their responsibilities. These males are behind, but this doesn't relieve women, or girls, rather, of their responsibilities.
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