What are your most embarrassing naked moments?

One time when i was getting changed at a public pool ( i'm a girl) and i normally change with a towel around me, but since there was nobody there i wasn't worried. After i had taken off all my clothes i realized the zipper for my bag with my swimsuit was stuck. As i was bending over to fix the zipper my english teacher walked in and got a great view of my butt. I quickly turned around and covered myself with my backpack, then sprinted for the bathroom stalls to get my suit on. Later when i was leaving i saw my teacher getting changed under her towel. When she noticed me she said she felt bad for seeing my butt and lifted up her towel to show me her butt. I'm glad she was just as embarrassed as i was

I haven't got any embarrassing stories, but it's nice to know there are still teachers that are sensitive yet down-to-earth and good-humoured (no doubt an experienced mother herself).