Day 21: Tuesday

I went to an adult toy store today. I put on my most serious clothes and my most self-assured expression. Thinking of Anna certainly helped in that department. Well, anyway, it went without a problem. You see, Anna had decided that she wanted a vibrating butterfly from her allowance. And naturally she volunteered me to buy the thing. Well, I already had an idea how to use it, so I gave in and went to buy the thing.

In case you don’t know, a vibrating butterfly is a small but powerful vibrator that can be strapped to a woman’s clit and secured there with rubber bands. The advantage is that it does not fall off during sex, while providing powerful stimulation. The disadvantage is that when a woman is tied up, she cannot remove it on her own. Did I just call that a disadvantage?

I’m not sure what Anna thought we were going to do with her new toy, but I hope she didn’t plan on any pain-free orgasms. Because obviously, that’s not going to happen.

No, what I do is tie her to a chair and strap the butterfly to her clit. I don’t turn it on, yet, because first there are rules that my sister needs to know about. The first rule is that for each orgasm that she has, she must pay with five hard slaps to each tit, each ass cheek, and to her pussy. She doesn’t have to pay immediately, but rather afterwards for all orgasms at once.

The second rule is that I’m going to hold lit candles above her tits while the butterfly is running, and she may only blow them out after she cums. And when she cums again, I’ll light them again. So every second orgasm will be by candlelight, so to speak.

The third and last rule ist that we will do this for exactly one hour, no more and no less.

When I tell these rules to my sister, she readily agrees. I’m not sure why, it’s not like I asked her ... aaaaaand there’s the one-eyebrow-thing again. Well, we will see who has the last laugh!

I double check that Anna is securely fastened to the chair, then I switch on the butterfly. Judging by her sudden rigid posture, it must be quite intense. And then I up the game by lighting four candles and holding two over each of her breasts. She orgasms quickly after that, which allows her to blow out the candles.

So her next orgasm several minutes later is more relaxed. But now the candles are back, and for good measure I remove the wax from Anna’s chest first, so that I have a clear target area. Her third orgasm takes a bit longer, and the fourth (without wax again) even longer. By now her clit is already very sore, as she urgently informs me. I just glance at the clock (still more than half an hour to go) and shrug.

Orgasms number five comes much more quickly again, probably due to the combined effect of the hot wax on her irritated skin and the butterfly vibrator on her sore clit, which makes the vibration almost more painful than pleasurable. Of course, for my sister, painful is pleasurable.

The next two orgasms (six and seven) also come (or cum?) fairly quickly. But by now, my little sister is clearly in distress as the merciless vibrator tirelessly hums away at her raw nerve centre. It takes her almost 10 minutes to reach another peak. And now the candles are back, and we have 12 more minutes to go. Anna has tears in her eyes, but she takes it like a trooper. Although I’m not sure that she would take it as well if she weren’t tied down...