If you don't wear a condom with women (of the night); you because you don't want to, or she says she doesn't care, then either or both of you can be considered irresponsible, with each of you potentially susceptible to catching something that might not be the ultimate happy ending!
And possibly making matters even worse if you are multiple-timing your wife or g/f.
There should be another sub-forum below the Pub - The Gutter!