New to a job as a hotel receptionist years ago. Starting an early morning shift and I was told to go and get a set of keys from the previous shifts night manager. Night managers had their own room in the hotel and slept overnight.
I knock on his door, and hear a sleepy mumble inside "yep, just a sec". Male manager, used to the routine, didn't bother getting dressed for this key exchange. Undies on, but sod all else - but I didnt know this.
Night manager thus opens his door in just his y-fronts, hands me the keys and proceeds to give me a quick sleepy update on something from the shift before, then shuts the door and shuffles straight off back to bed again.
Apparently, he always did this. Couldn't sleep with clothes on, and couldn't be arsed putting clothes on just for several seconds of communication. So he always answered the door in just his underwear.
I go back down to reception and immediately exclaim to the rest of the team on entering recrption "why didn't anyone tell me that Brian comes in his pants when you knock him up?!"
Obviously meant to say "why didn't anyone mention to me that Brian answers the door in just his underwear when collecting the keys from him" but I was shocked and I just blurted it out.
And an older Australian couple were stood there, checking out. It was 6am and we didn't normally have people checking out that early (country retreat nestled in the countryside). I still remember the look on the womans face inparticular. I could die all over again as I realise how I've phrased it terribly then try to dig myself out of that very big hole to these guests, and then them scuttling off wondering what sort of sordid place they'd been staying at.
Colleagues never let me live it down.