I’m such a lucky sister to have a brother who is willing to be my personal trainer for free. I know how popular you are. You’re always booked solid! And you really get results. Your clients are all in amazing shape! They’re all women, too, I’ve noticed. You must have some special training program to get them so motivated. I wish you’d tell me what it is, even if it is dirty.

That’s when you reveal that it’s a simple reward-penalty system. If you give me a challenge, say 100 crunches, and I can’t do it, then I have to do something for you. However, if I can, then you have to do something for me. It doesn’t sound so kinky until you tell me what the rewards and penalties are: tit fucking, blow jobs, and full penetration of my wet pussy.

You can hardly believe it when I practically start begging you to give me a challenge. You agree, but you’re not going to make it easy on me