Oh, this is a great question!
I will have to think about it more carefully for a follow-up post, but my immediate thought goes to seeing my mother-in-law naked the first time. Talk about a shock! She is a very religious, conservative woman, but my wife and I went to her parents' house early on in dating, we go inside and we hear her mom say hi from the bath. A few moments later, she walked out into the living room completely naked while drying her hair. She was mid-50s at the time, and looked like she was 20yo if you didn't look at her face. Of course I have seen her dozens of times since then, and even 20+ years later in her 70s, she still looks like she is mid-30s naked. It still catches me off-guard how such a conservative extremist loves being seen nude!
I get quite jealous of those who have seen their sister-in-laws nude while I haven't seen my own sister-in-law nude, but that is for other thread topics.
