The day after, my brother called me and asked if I was thinking the same thing he was. I of course said yes. We discussed what we wanted to accomplish, what our limits were, and ideas of how to get there. I gave her a few days before bringing up that night and when I did, she was embarrassed, but thought it was fun and hot. That led to me making little comments here and there and when my brother came around, he would too. He'd say things like, "that was a great teasing show, so when is the real deal happening?" Other times, he would say things like, "you got me all excited and left me hanging. You owe me one." Every time this happened, she would blush, and her body would get hot.
I started pressing more. Telling her how sexy and beautiful she was and reminding her how much we enjoyed watching ourselves in the mirror. We didn't just have a great sex life, but we were great at it and looked good doing it. I'd tell her it was a shame that we weren't showing her off. While having sex, I would mention someone looking in the window, and eventually started mentioning someone sitting in a chair touching themselves. It always pushed her over the edge.
Over time, these conversations would come out more and more, but mostly when I had drank enough to bring them up. One night when my brother was there and we were all drinking, he bargained with her. If he hit an unnamed goal, she'd let him watch. Turns out, a few months later, he did it. He did what she asked and he called in the debt. She never thought he was serious, but he was and I encouraged her to keep her deals. After some considerable urging, off to the shower she went, while he and I were pounding shots.