I woke my sister up the next morning around 8 am with a sensuous kiss to the neck, just underneath her right ear. I then began to kiss and nip her earlobe with teeth, gently.
She woke up quickly and her voice was full of regret.
"Listen, last night was pretty fucked up. I can't believe what I...what we did. This is so wrong."
I was a touch indignant. "It felt pretty great to me."
I returned to kissing her neck, moving upwards again to the earlobe, then sticking my whole tongue into her ear, which made her shiver. We kissed passionately, shifting positions, sliding one side to another. She injected her own tongue into my mouth, and I sucked it, forcefully, but not painfully.
We'd fallen asleep naked, so there were no clothes to remove. But we were in a very small room that had been built one hundred years earlier, when people were proportioned much differently. As I rose on top of her, resting semi-comfortably on my knees, I had to avoid hitting my head on the ceiling. She closed her eyes and as I had gone instantly hard, I manually inserted myself into her. She began to rock back and forth on my cock.
We both knew we had to be silent, so as not to wake up our parents. And we were supposed to be staying in separate rooms, presenting another heavy risk. To be caught in the same space, naked in each other's arms would be difficult to explain. But there was a kind of taboo pleasure involved that we both invited, in spite of it. Peering downward, I took a moment from pounding her to take in her older body.
It was thinner and more compact than it had been in her twenties. Her face was less fleshy, as was her ass. She'd always had an athletic build, but it was obvious that years of surfing and rock climbing had firmed up her body. She was sexier now than she had been ten years ago, and that was saying a ton because she'd been super-hot even back then. She was heavily toned now, which accentuated her curves.
"Pull my hair," she whispered. "Are you sure?" I whispered back. "Yes, do it! I have a high threshold for pain. I can keep quiet."
She bounced, ever so gently, up on down on top of me, rotating on my cock. And the whole time I pulled hard on the back of the ends of her hair with my right hand. It was long and dark brown, about halfway down her back. She panted with great force. "I've wanted to give your dick a ride for years. I've wanted to feel it buried deep within me."
I was quizzical. "Then why didn't you do it before now?"
"Because," she said, exasperated, "I never knew how to ask. I never knew if you'd even be interested, or think it was okay."