I glanced down the alley as I walked by and saw this group walking down. Often I try to do a quick, unobtrusive 'spy-cam'/voyeur style shot, but this time I decided to just boldly aim and shoot. Two very wary, not quite hostile looks from the guys; one who doesn't seem to care and one who definitely isn't have her picture taken today, thank you very much.
I heard what might have been a shouted, "Hey!" but I'd already walked and didn't look back to see just how offended they might have been.