Years ago, while out with my (now) wife and best friend, we were drinking at a bar and the topic somehow turned where my wife said "well i have really nice nipples". I didn't think much of it other than "man, that was hot". But then like 2 minutes later, she privately pulled out one tit and said "should i show him?" And before I said "yes", she called his name and his jaw literally dropped. After she put it away and we talked and laughed about it, she immediately said "I can show you guys again you know" - as if she couldn't wait to pull it out again - which was so hot to me. And then she just pulled it out again while sitting face to face with my friend on neighboring bar stools while I stood next to them! I was SO turned on, I told her I wanted to go home and play truth or dare with him or something. She agreed. Before we went home, we stopped at another bar. This time, she called MY name at one point and said "look" and pointed down to here tits. They were both discretely out and my friend's hand was tweaking one of her nipples. He was staring at me like "dude, i did not initiate this". It was fucking hot. She's never done anything like this before but clearly was listening when I told her showing her off is my biggest fantasy. Then we went to a restaurant together and sat in a bench, wife in between us. At one point they started making out and his hand was going down between her legs but she freaked out and stopped. That's where it ended.
YEEEEARS later and I still think about this. I'm constantly trying to invent scenarios where she does hotter and crazier things with him - "friendly" game of truth or dare one night after the kids go to bed, or coming out of the shower with her towel and we tease her to show us and on a whim she just confidently opens it up and wiggles for us naked. SOOOO many possibilities.