We were watching
My wife and I moved into a new neighborhood recently and met many of our neighbors all who are friendly. A few weeks after moving in my wife came to me a little upset. She said go look out the bathroom window into the house next door. The woman from next door was masturbating with a toy of some sort. Her lights were on, the shade was up and this woman was going at it like crazy. My wife came back into the bathroom and asked what should we do. I said maybe she dosen't realize we can see her, that's bullshit my wife said, she's probably doing it on purpose. On purpose for what I asked. Maybe she wants you she said, I said maybe it's you she wants I said, let's just ignore this, if it becomes something more we should tell her we can see her. I look for her doing this everynight. She's not bad looking and she made me horny, but I couldn't admit that to my wife. So far it only happened that one time. I think in reality she never thought to pull the shades down in her haste to orgasm. My wife wants nothing to do with her after seeing that.
Start an exhibition match
I think you can assure your wife that it isn't you she's after in particular. I think she's just an exhibitionist. For her the idea of being watched by anyone is exciting. I have the same feelings sometimes. She would probably love it if you'd just keep it to yourself and watch her.
Yeah, sounds accidental. Too bad. If it happens again, let us know.
If it only happened once it was probably accidental. If she was advertising herself for you and/or your wife she would probably do it again. I would keep my eyes glued to the window though, and if it happens again I would let her know what you saw and that you liked it. Might turn into some good action on the side, if you are into that kinda thing.