Men With Sisters Less Sexy Than Men Without
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Does your boyfriend have a sister? Two sisters? Ten sisters? Are you both literally rats? If so, it’s possible you don’t really want to have sex with him, a new, rat-based study reveals. Male rats raised among mostly brothers lure more females and have more rat-sex than their sister-raised counterparts — although they don’t know nearly as much about tiny rat clo-othes, etc!