My sister in law was a stereotypical nerdy girl. She moved out east after college and started working at the same place as me. I actually introduced her to my then girlfriend's brother. She's on the small side - just barely over 5' tall. She has nice tits that one would call fun bags (just enough sag to give them some extra sway).
After we were all married, we would socialize pretty frequently and occasionally travel together. On one trip we all had to stay in the same room at my in-laws condo at the beach. Long story there but the short of it is that where we went to sleep, we woke up. I have a fairly big cock, there's no two ways about it. Despite my best efforts, it gets out during the night. If I happen to be on my back in the morning, the sheets take on the appearance of a circus tent. I woke up one morning to exactly that. As I began to stir, I heard Mary Jo (the sister in law) gasp and quickly turn so her back was to me. She was peeking. She got caught. We both knew it. But that was it though, we never mentioned it again.
About a year later, her husband had apparently taken a picture of her in her underwear. For whatever reason, she decided to show it to us. There she was, arms spread wide in her fairly sheer bra and panties. Big round areola showing through along with her big 80's bush. Maybe she wanted to return the favor. Who knows? It was kind of hot but a little awkward with my wife sitting right there.
Time marches on 20 years or so. We all have our strong points and one of mine is fixing things around the house. Plumbing, electric, drywall, tile, etc. Mike and Mary Jo had bought a condo at the beach that needed some repairs. Being the nice guy that I am, I readily offered to help them out. It was a long weekend so I got there on a Thursday. My wife decided to not make the trip in favor of seeing some other friends from out of town. Mike had a business trip to the west coast and wasn't getting back until Saturday afternoon. I went about my thing, changing out ceiling fans, adding dimmers, putting a backsplash in the kitchen. I was pretty much at it until late in the evening on Friday. Given the long day, I took a shower and went to bed.
A couple things contributed to what happened next. First - I sleep in the nude. I don't even own a pair of pajamas. With the whole nighttime erection thing that guys deal with, most sleepwear is just too constricting. Second, the one thing I hadn't got to fixing yet was the door latch on the guest room door.
I guess Mary Jo is an early riser. I started waking up around 9 in typical fashion. Nude and erect. It was warm so at some point I had totally thrown the covers off. So there I was, flat on my back, with all my fat 8 inches of glory straight up in the air. I opened my eyes and looked to the door that was ajar and there was Mary Jo standing there with her mouth hanging open. We locked eyes and she froze, but made no move to turn away this time.
I thought to myself "what the hell" and in the most casual voice I could muster said "You can come in for a closer look of you want."