I was lying on my bed about nine pm reading the book that my aunt had given me at my seventeenth birthday party earlier. Yeah, real paper, not a tiny screen. My door opened without a knock and my fifteen-year-old-sister Cami and her best friend Kelli entered wearing robes like they were going to the bathroom.

“We wanted to wish you happy birthday again,” my sister said and they dropped their robes simultaneously. She was a brunette with conical tits standing out and black curlies down below. Kelli was blond both places with a bit more underside curves to her breasts.

Cami pulled my sheet off and took away my pillow. I just watched to see what would happen. She clambered up on the bed and straddled my face, asking without words as she lowered her pussy towards my mouth. I’d done that a few times with my current girlfriend, if thats what you could call a slut who your buddy and at least one other guy were also dicking. Anyway Cammi liked it judging from the sounds she started making.

My parts were just hanging out and I’d sort of forgotten about Kelli unti I felt her mouth on my rock-hard-rod. Again, an amateur compared to my girlfriend but I was also glad that the same had given me a birthday bang that afternoon. Took the edge off.

I couldn’t see what was going on down below, just feel, but she got on the bed and I wasn’t surprised when a hot cunt began engulfing my seven-incher. She eased herself down, apparently to stretch her twat to take it, and then began moving up and down slowly.

I had my hands on Cami’s tits but reached around with one to get a handful of Kelli’s. She let out a moan. My sister gave a shudder and a squeal as my tongue got her off. Her juices got a bit more abundant. My cock shot into Kelli, with a spreading glow from my crotch and my fingers diddled Kelli’s clit so she could climax with me inside.

They were laying on either side of me and said they were both virgins when they entered the room. Cami turned off the light. I was awakened sometime later by one of them riding me. A tit-grip told me it was my sister but Kelli kept my mouth busy with hot tongue kisses and got on board after Cami got hers since I hadn’t cum yet. She got it though. I hadn’t expected more form my sister because of her commenting about incest but there must have been too much temptation.

They were gone in the morning to keep up appearances by being in Cami’s room. Our folks left to go shopping after breakfast and the two hotties took me back to bed for more screwing even though my birthday had passed.

When I asked about birth control since each had at least two loads of my abundant sperm deep inside, they said these were safe days. I squawked, “You’d better get something more reliable than that!”

It’s a month later and I’m fucking Cami at least once a day. My best friend who knows what’s going on wonders if she would do him too. Kelli gets my dick two or three times a week and I’ve heard she has a steady boyfriend now.

Cami’s birthday is a few weeks away. How many guys would it take to get her fucked sixteen times on that special day?