[busgusti]

My experiences are quite different from Gnome's.

My wife (let's call her M) and her twin sister (let's designate her F) come from a conservative/religious family, so modest dress is the norm. No plunging necklines or skimpy clothes of any kind.

Over the years I've cultivated a "comfort level" with my wife's sister so on various occasions she has let her guard down.

The first time I had occasion to see her totally topless (although I had already seen nipples here and there by then) was about 12 years ago. M had bought a whole load of clothes and, being the same size* & shape (and with the same taste in clothing) as her sister, had invited F over to try some of the things on and see if she wanted any of them.

*Different bust size (F is considerably bigger)

It started modestly. We were all in the living room and F would step in to the other room to change shirt, then come back to show us and discuss with M. This went on for a couple of times, while M would just pull off her shirt right there and try the shirts on to show F. F was getting bothered by having to walk out each time. After a few she just said "busgusti don't look" and after I turned away she changed right there in the living room. So of course, being the good brother in law that I am, I kept my eyes averted. For the first one, maybe also the second. Let her get comfortable. A few shirts in and she didn't remind me to look away. Just peeled off her shirt and changed in front of me. Then the skirts. By this time both M and F were just ignoring my presence and F just got changed right there in the living room, as if it were her own house. Naturally, I just went about my own thing without calling too much attention to myself and enjoying the odd view of F in her bra or panties.

Now here comes the interesting part. It turns out M had also bought a couple of new bras and had gotten one for F to try. They're of totally different sizes so those are not interchangeable between them, but my wife swore by these new bras ("they're soooo comfortable") and had picked one up for her sister.

As soon as the talk turned to bras I made myself scarce, keeping out of the living room in the hopes that F might just try that on right there as well. The front of the house is open plan so I wasn't really behind any walls, just distanced from them but could easily turn and look their way should something happen. F was comfortable, but not comfortable enough. The next I heard was "I can't change here, busgusti is right there" and she removed herself to the other room to try it on.

F came back and they discussed the bra, but seeing how it was the last item to try on, I figured the show was over. I went in to another room and left them totally alone in the living room, leaving the door to my room open so as to still be able to hear snippets of their conversation. After about 20 minutes, their talk returned to the topic of the bra with M saying she liked it and F saying something about her other one being better. 'This is interesting', I thought. It sounded like F was about to show M the bra she was wearing when she came over that day. I realized I needed to time this perfectly if it was to succeed.

I left my room quietly and started to make my way back to the living room. Their talk became clearer and indeed F was saying something about her original bra. And just when I thought it would be the right moment I stepped in to the living room and there, clear as day, was F totally topless and holding her bra in her hand about to put it on.

They're a great pair.