So I was in the military years ago and we had this really loudmouthed, obnoxious dude in our shop who always acted like he knew everything. Friendly guy, just hard to be around. Anyway, he started getting really friendly with this officer chick (pretty cute, actually) and we were enlisted. That's a big no-no. They got told by our Commanding Officer to chill the fuck out and stop being so friendly with one another, since she was married (her husband was a complete ass, to be fair). They agreed and didn't really talk much in public after that.
So one day, a year or so later, I was about to leave work and could not find my goddamn water bottle. I had left it somewhere on the ship and we had run around doing maintenance all over the place that day, so I retraced my steps. I got to one of our more out-of-the way workspaces, opened the door, and this officer (who had absolutely nothing to do with our equipment and had no reason to be in that workspace) pops out from behind a big peice of gear wiping her mouth and going "What are you doing in here?!" frantically. I was kind of confused, but then I realized I couldn't see around a corner of the room. I instantly knew what was going on and I just kind of laughed and explained I was looking for my water bottle, and then loudmouth-dude popped out and was trying to explain something to her about a fire extinguisher. It was pretty comedic, but very obvious she was blowing him.
Turns out, they'd been having an affair the whole time. Anyway, he cought up with me later after I was about to leave and go home (water bottle in hand, thank you very much) and asked me if I was going to say anything. I assured him I didn't care and wouldn't say anything to anyone. I didn't. I did, however, email myself a detailed account of what had happened on Gmail so I had a timestamped account of the story in case they tried to accuse me of some crazy shit.
They never did. They did, however, proposition me to DP her a few months later. Tempting (she was really, really cute) but I declined. After I got out of the military, I heard they'd both been kicked out for fraternization.