This is about my ex-GF, of which I have written here before (like a few posts before). She was a chronic, yet unaware, flasher. Here are two more occasions that I remember clearly.
First one was on Sunday during a family visit, a long time ago. I got to her house maybe at 9am. She opened the door and let me in. She was wearing her pajamas. Nothing sexy, but actually the opposite. She told me her father was coming (her parents were divorced and she lived with her mother) and should arrive shortly, so she left me in the living room while she went to her room to get ready. After a while, her father arrived and we started talking (we got along very well). After another long while (you know how women take time to get ready), she finally got out. She was wearing a very nice (and very short!) denim miniskirt with a white t-shirt, which both showed good cleavage and allowed her white lacy bra to show through the fabric. Since her father was next to me, she sat down in the sofa in front of us. I do expected some flashing when sitting down, as most girls wearing very short skirts occasionally do, which of course happened. But I could never have expected she to just keep her legs uncrossed, if a bit spread. Definitively it was another cotton g-string, but this time it was white with a green tic-tac-toe pattern in the front. Very cute and sexy! For the next few hours I had this view, all while her father was next to me and obviously could see the same as me. It was very difficult to have a conversation in that situation
Second one was much shorter. We were going to an hotel that night, so I picked up from her house in the afternoon. She was wearing a white miniskirt about mid thigh. She was wearing a blue t-shirt, but nothing out of the ordinary. No fancy cleavage or anything. As soon as we got out of her house, she told me "I have something new to show you". She wouldn't tell me what it was, but instead told me to "just wait and you'll see". I stopped a taxi and let her go in first. I got a very sexy view of some black lacy bikini-style panties. Even her pussy lips were visible through the lace. Inside the taxi, she sat down sideways, facing me and giving a good flash. When we got to the place, I got out first to keep the door open for her, while getting an eyeful of her panties. What a beautiful view. So there went her surprise, though she didn't even notice.