I knew it was wrong to think of her that way, look at her that way. But I couldn't help it; my twin sister was beautiful, and I wanted to be with her, to have her, to shove my cock inside her—and then for her to make me her slave. I'd had these feelings for a long time, but coming back from my first year at college seemed to make them ten times stronger.
I used to just listen to her masturbating, but a few weeks ago I built a little periscope-like device that would connect between my room and hers, so I could actually watch. She did it so often; almost as often as I did! Not that I'm complaining; it gave me plenty to see. By now, I was used to her routine, and I could time myself to it, not letting myself finish too early. She still usually lasted longer than me, but is it my fault that my sister is a master of the multiple orgasm?
She always started by taking off every last article of clothing, even her glasses and the necklace she always worse; then she would sprawl out on her bed, spread her legs, and slowly slide her hands down her body, starting at her neck, moving across her breasts (staying for a little while), then down her stomach, past her pussy—the restraint she showed!—and on down her legs as far as she could go, then back up, ending with one hand over her pussy and the other squeezing her breasts.
Of course by now I always at least would have my cock sticking out of my pants and my hand wrapped around it; usually I would take of all of my clothes and stand at the periscope naked. I'd try to synchronize myself with her; as she pumped her finger in and out, I'd slide my hand up and down. As she massaged her clit with the palm of her hand, I'd press my finger into the base of my cock, right where it met my balls. Even if she'd never know it, there was always a sense of give-and-take in this little sessions.
But this time, things were different. I found myself getting much too excited, much too quickly; I let go of my cock, but it barely helped. I felt so hard, so horny; I didn't know what to do with myself. So I guess I did the craziest thing I could possibly have done. I opened the door of my room, walked down the hallway, and walked into her room, closing the door behind me. I was naked, hard, and more ready than I think I've ever been.
She gasped in surprise, and instinctively covered herself with her hands; but when she realized I was naked too, her shock was replaced with something more like puzzlement.
"I... heard you," I said. It was sort of true, I guess. I did hear her, among other things. (And I could hardly say that I'd been watching her via homemade periscope for weeks now, using her like free homemade porn.) I didn't explain that I now wanted to fuck her; I kind of figured it was obvious.
Though she did seem a little slow on the uptake. Maybe arousal damages your ability to draw logical inferences? "I guess you were... too?"
