Karma. It's a thing.
I'm not sure of the backstory to the photo a colleague posted on Facebook... but, it would appear that someone had been doing some cheating... and someone was doing some cheating despite knowing that someone was married... and so someone decided to post a giant sign calling out said cheating in a very public way...
Is this ever okay?
YES NO POLL TIME... take a look... think on these things... then speak your mind...