Sister's Surprising Discovery

"A girl's got to have secrets!" replied Beki with a smile.

"God, I can't believe I used to think you were an innocent virgin till this afternoon!" I said to Beki in jest.

"Whoever said I was a virgin?" said Beki with a smile on her lips.

Once again, I did a fish impression as my mind reeled from thoughts of Beki not being so innocent, her joke (I thought) of us both having sex with our step mum and visions of her and Naomi involved in a lesbian tryst with a strap on dildo.

"I see someone's come back to life!" said Beki, reaching for my cock which had indeed regained its rigidity.

Beki climbed on top of me and began thrusting herself up and down on my dick with renewed vigour. She bent her head and whispered in my ear. "I still have one virginity that I might give you if you are really good!"

If I hadn't cum twice this evening already, I may have lost it there and then. I couldn't believe it, this day was like a gift that kept on giving. What started out as potentially an awful time was, for me at least, becoming absolutely awesome.

Beki reached to the nightstand and took some lube that I kept there, (usually out of sight, but she had walked in on me preparing to have a wank to some porn). She climbed off me and liberally applied some to my cock before encouraging me to apply some lube to her back passage. Finally satisfied, she lowered her arse down on my rampant dick. I had my cock up my sister arse! I couldn't take it in. Beki grimaced in discomfort but she was determined. Gradually, more and more of my penis disappeared into her bowels until she was fully seated on my erect member.

"That's it! Fuck my arse! God, I love it" she squealed.

This was definitely the best thing that had ever happened to me. Beki was like a wild woman riding my dick to heaven.

"Fuck me brother! Pump my tight arse!"

I grabbed hold of Beki and flipped us both over so she was bent over the bed and I began to ream in and out of her tight sphincter. I don't think I'd ever felt anything like this as I pummelled her bowels for all I was worth. We'd both cum more than once, so this was going to be hard, rough sex. I pulled out and gloried in how much her bum hole was gaping before I thrust violently back into her back passage and resumed reaming her like there was no tomorrow.

"Oh God, fuck my arse with your big cock! I love it!" squealed Beki as I somehow found energy from somewhere that I didn't know I had.

So lost in delirium were both of us that neither of us heard the door downstairs opening as our parents returned home earlier than planned and were in the midst of a loud argument.

I suddenly heard my step mum's voice on the landing.

"God, your son is watching porn without headphones again! You really should speak to him before he corrupts Beki!" she chided our dad.

Beki and I went quiet and still in total shock as we looked to the closed bedroom door.

"Sorry dad, I'll turn it down!" I shouted as I willed them to go away.

"Please go away!" I pleaded silently under my breath. Beki didn't move, my cock was still buried in her arse and we could do nothing but pray that our parents would just go to bed and tell me off for watching porn in the morning.

"Nothing to see here. Just go to bed!" I willed them through the walls. Did I see the door handle moving?

Nobody came in. Our secret was safe. For now at least!

I expected Beki to just slip quietly away, but as she pulled herself off my cock she saw it was still swollen and hard.

"Can't have you going to bed with blue balls!" she whispered in my ear as she put a finger to her lips and sank to her knees. I watched in awe as she slipped her mouth over my swollen glands.

I was painfully aware that my cock had just been in her bum.

I was very painfully aware that our parents were the other side of the wall, although I relaxed a bit as I heard them begin to have makeup sex, apparently oblivious to what was going on in my room.

I came in minutes under my sister's silent gobbling of my cock at the end of an amazing evening.

Beki kissed me on the cheek. "Sleep well brother," she whispered as she crept out of my room for the night. I lay listening to the sounds coming from my parent's room as I reflected on everything that had happened and wondered what the future would bring. After today, I knew that any fantasy could come true.