I woke up with her breath in my ear and her hand on my erection. I moaned in pleasure and she giggled. "I think I should be insulted, stud, because you fell asleep."
"Only after you did." I said sleepily and she giggled again.
"I've been awake for a while, just watching you sleep, thinking about what we've done and" her voice dropped to a whisper "what we're going to do." She shook her head and softly added "I still can't believe that I'm in bed, with my son, or the fact that I'm so very wet thinking about us making love." She glanced down at her hand, which was lightly stoking me, and stopped long enough to use her index finger to collect a bead of my pre-cum. She looked at me as she put the finger in her mouth and my cock twitched as she closed her eyes and gave a small moan.
She opened her eyes as she lowered her hand to again lightly stroke my hardness and gave me a mischievous grin before saying "Yummy." She rested her chin on my chest and we stared at each other in silence until I shifted into a slightly more comfortable position.
"Can I ask a question, mom?" I asked.
"Of course you can, son." she answered.
"I love the fact that you want me to make love to you, and I certainly don't regret anything we've done but..." I trailed off not really knowing how to say what I wanted to say without sounding like a jerk.
"Why?" she finished my sentence and I nodded. She sighed and stopped stroking me, laid the side of her face on my chest, and was silent for a long moment. She suddenly sat up and, much to my surprise, giggled again. "I guess you can say it was because of your father. When you graduated high school I took a picture of you with your father and after the film was developed I realized how much you two looked alike. I told your father in passing and he waited until that next Saturday to surprise me."
She stared at something only she could see, a small smile playing across her lips, and continued "Saturday night was our special time of the week when your father would force me to do things. That night he tied me face down on the bed, blindfolded me, told me not to go anywhere, and left the room. I don't know how long he was gone, but it seemed a long time, and then I heard the bedroom door open."
"Did you know your father was very good at mimicking voices?" she asked out of nowhere and I shook my head no. "Well, he was, and he made his voice sound like yours when he said, and this is a direct quote, 'Daddy said you were my mommy slut for the night and I could do anything I wanted with you.' "