I was really disappointed. For months I had been anticipating my big sister coming home from college and jumping into my bed. For months I had been planning how I would fuck her and how surprised she would be when she found out what I could do and how much I had grown.

Almost every day this spring I had been mounting a full grown woman after I cut her lawn, and every single one of them orgasmed and praised my efforts as well as giving me some money, in fact a lot of money. I was ready, ready and eager, eager and really well equipped.

I stood looking at myself in my sister's full-length mirror. I made bicep muscles and admired my chest expansion, the firmness of my abs, the swell of my thighs and, most of the all, the size, shape and thrust of my swelling woman pleaser and bulbous scrotum.

In this school year I had gained fifteen pounds, grown three inches taller and my cock, which had barely been six inches long when my big sister took my virginity last year was now well over eight and thick as a hoe handle, just as hard too. When really aroused it not only stood straight out from my loins, it actually rose above the horizontal and pointed upward, slightly curved, it head dark and threatening. I had produced screams of pleasure from some full-grown women.

And yesterday at the airport, there they were, my luscious sister and this pale blonde with long legs and big, jiggling boobs. A girl from Iceland, my sister told us as we got her luggage, whose family couldn't afford to pay for her airfare so she was going to spend the summer with us. I had to admit that Jona was very pretty and that my cock surged when I watched her globular jugs bounce freely in her sweatshirt, but I lusted for my sister's wonderful body and talented cave of pleasure. It was where I had enjoyed my first lessons.

The worst thing was, I concluded wrongly, that the buxom blonde and my sister were lovers. My randy sister had become a lesbian. They slept in the same bed, and last night I couldn't help but hear their lovemaking, their groans and the squealing springs as they did whatever they were doing together. My imagination knew no bounds. And my cock went limp.

I had even been doing Kegel exercises regularly and could stop my piss stream at will and hold back an ejaculation if I wanted to. That ability drove some of my matronly customers wild. On one lithe woman I had humped for nearly a half-an-hour, clamping off three urges before I let her have it, and she nearly died with pleasure, screaming and writhing under me. She gave me a hundred dollars. I did Kegel contractions off and on all day in sets of ten.

I put my hands behind my head and flexed my groin muscles and my cock jumped up even higher, beautifully curved, almost like a banana, the head purple and blunt nosed. I did some PC crushes and watched it jump. A couple of my customers had told me that it felt like a bulldozer or snowplow when I rammed it into them. The blunt head was sort of shovel shaped, a split helmet, a prod, a fucking spear. My pride and joy, mostly joy. And the head ridge; it really caused screams when I pulled back and dragged soft flesh with my rigid ram.

I had crossed the room to get some clean underwear when my sister and her friend came in, sat on the side of my bed and smiled at me as I stood there, naked, with a pair of boxers held between my legs, half hiding my painful erection that stood out a half-foot in front of me.

"Billy," my grinning sister said, "what have you been doing?" The voluptuous blonde giggled.

"None of your business," I said, turning my back to them and pulling on my shorts. I wiggled my cock straight up against my belly and hoped the head wouldn't pop out above the waistband. "What do you want?" I asked, pushing it sideways.

I turned and looked at Jona who was biting her lower lip and blinking at me. 'That," she said, "that nice, big, fat, hard thing."

"We like each other," my sister said, "and we have fun in bed, but we have agreed this morning, we need a male, a hard cock, and you've got just what we need."

"I thought you guys were lovers, lesbos, you know," I said, confused.

My sister shook her head. "Nope, just playing, making do. We were both getting all we needed at school, but between boys, we pleasured each other. There's nothing wrong with that, is there?"

"Maybe," Jona said, "just for the summer, until I get to know some boys around here, you could, you know, do us a favor. They say I am very good at fellatio." She licked her lips and my prick jumped.

I nodded, swallowed and blinked at them, a pair of very pretty twenty-year-olds sitting on my bed in tiny babydoll pajamas, asking a fifteen-year-old for sex.

"Who's first?" I asked, feeling my voice almost breaking.

"Do Jona, with final exams and everything, neither of us have had a boy this month." My sister stood and pulled the blonde girl's top over her head and hurried from the room.

Jona's breasts were kind of pear shaped, hanging from her chest but rising to upright nipples in dark circles. They were large, full, firm and lovely. My already rigid cock got even harder. "How do you like to do it?" I asked her as I stepped closer and could see that her nipples were erect, jutting out like fingertips and the area around them was kind of pebbled. I reached down and filled my hand with one breast and lifted. It was warm, firm, and heavy.

She looked up at me and smiled as she pulled down my shorts. "Slowly," she said. "Oh, how beautiful, how big, stor, grand." She reached out and stroked my ram as I cupped both her big boobs and squeezed gently. She shivered, and I reached up under her arms and tossed her up onto my bed and pulled off her tiny panties.

My cock was dripping as I got on my knees between her long legs and admired her carefully shaved mons. Her outer lips were parted and quivering, already wet, fluttering as pink showed from within. I would not have to lick or finger her; she was ready. She raised her legs and spread her knees. I pulled my pillow down under her rump, set my blunt-headed prong at her seething hole, grinned at her and pushed.

She arched and made some very odd noises, like 'gee-gee' and 'ah, ah, ah' as I slipped it into her, very slowly all the way into her until my public hair and my tensed balls were pressing on her groin, grinding us together, rubbing bones against each other, massaging her whole slit. Then I flexed it, and she rocked from side to side and cried out loudly as if she had been shocked. I growled and crushed her clit.

In came my sister, "Don't you hurt her," she yelled, and then she put her hand to her mouth as Jona smiled and wrapped me in her long legs and humped me hard. I heard the door close as we began moving together, just very short, very quick thrusts, an inch or so, getting settled in, making sure I was as deep as possible, tearing her open very quickly, feeling flesh parting, arching up and thrusting deep.