This TIFU happened about 4 years ago, and still keeps me awake at night out of embarassement..

Me and my girlfriend at the time were staying at her grandparents house, and this particular afternoon was pretty chill. I was sitting upstairs on one of the recliners, reading a book or scrolling through Reddit, when out of the corner if my eye i see someone come upstairs and stand next to me, looking at the bookshelf directly behind me

Now of course, my ex and her mother had very similar figures. And on this day her mum was wearing a pair of my girlfriends skinny jeans, for whatever reason. Turning and seeing them, i of course get a sudden impulse to give those cheeks a cheeky slap

The absolute horror i felt when the voice that responded was not who i expected is a feeling i will never be able to shake. The worst part is, she assumed it was her 8 year old son, because he apparently has done that before.. so of course i had to TELL HER that it was me, and that i was so sorry and thought it was her daughter...

I dont think either of us made eye contact for the rest of the night..

TL;DR ex's mum stood next to me wearing her pants, and my subconscious was extra dumb that day