My partner and I are farmers. Given the rural area we live in, we look perfectly normal in jeans with dirt-encrusted knees and baggy sweatshirts with pouches full of tools. We wouldn't know fashion if it hit us over the head with a rolled up Vogue magazine.
Your question makes me wonder if you are asking if there is an ethical non-monogamy version of gaydar. I'm so new here I have no idea, but I tend to doubt there is. :-)