I could not believe how relaxed I was. I was in the shower, letting the hot water stream over my chest. I had just woken up maybe ten minutes ago. I closed my eyes and allowed myself to dwell on the images from last night that were stuck in my mind. It felt like I had had a great dream, but those usually come with a sense of disappointment when you awake to find they were not real. But these images were not from a dream but straight out of my memory.

My penis slowly began to swell as I remembered my sister, Jen, inviting me to rub myself against...