It started out just like any other Wednesday; I had class from eight till noon, and then I worked at the Bistro until nine. I walked home from there; it took about fifteen minutes. The full moon was just rising, floating just above the horizon like a great shiny penny, huge and orange. I was beat. Wednesdays are rough. I wasn't sure if Jennifer, my girlfriend would be home. Her younger sister Andrea was in town, and I thought they might be out having fun. Andrea was eighteen, three years younger than Jennifer and in her last year of high school. She was thinking about coming to the university where Jen and I went, so she was staying with us in our apartment for the week. I didn't mind, not one bit. Truth be told, I had already harbored some nasty thoughts about Andrea. She looks a lot like her older sister, and yet quite different.
Jennifer is a big girl. Not fat, not by a long shot; just big: tall and curvy, athletic and sexy as hell. She has beautiful long brown hair and big coy brown eyes behind her glasses. Andrea, on the other hand, is tall dark and lithe, almost waiflike. She stands almost six feet tall, an inch shorter than her sister (and me too), with small pert boobs and a tight little butt. She has short jet black hair, and always wears a black leather choker and black doc martins. A cute little punk rock girl with a sassy demeanor. It wouldn't be the worst thing, I had thought, if I happened to walk in on her taking a shower. Of course I wouldn't do any such thing, not intentionally. The idea, tickling the back of my mind like a little devil though, of having both lovely sisters in one bed just wouldn't quite leave me alone. Jen had never given me any reason to think she might be bisexual, or willing to experiment. Still, it didn't hurt to daydream. And I did daydream, walking back to the apartment that evening.
Nobody seemed to be home. No surprise, really. I opened a beer, and went to take a shower. I had a lot of homework, but nothing that wouldn't wait.
I thought I heard a noise in the bedroom, which is probably why I didn't blunder right in on them. I opened the door slowly, not really knowing what to expect. What I saw, however, was so far out of my experience that I didn't know what to think. I just stood there, not even breathing.
Jennifer was nude, on her hands and knees, facing the foot of the bed. Andrea was behind her, nude as well, but for the black leather choker, and a strap-on harness. Jennifer's strap on harness-- she was wearing the very dildo that had penetrated my own rear end just last weekend. I knew it well, it was about the same size as my own penis; but purple and ribbed. It was made of silicone, and buzzed delightfully when a small vibrator was tucked inside it. Now it was being rubbed all over Jennifer's pussy. Andrea was wielding her silicone tool aggressively. Thick gold rings pierced her nipples, and her small firm breasts shook delightfully as she worked her sister like a puppet.
"Did ya miss me Sis?" she cooed as she grabbed a big handful of Jennifer's long brown hair. "Did you miss licking my pretty little pussy? I've missed yours."
A pang of jealousy that I hadn't know I had in me rocked through my body, making my knees weak and my stomach ache. At the same time, my cock swelled in my jeans. I couldn't look away.
"Yeah Baby" Jen answered her, her voice thick and raspy "I missed my baby sister and her sweet little pussy. I've missed you so much Andrea."
"Did you miss my dick too?" Andrea asked, slapping Jen's shapely buttocks with the purple tool.
"Oh yeah Little Sister" Jennifer cooed "I've missed your big dick in my pussy so much."
"I've missed you too Big Sister." whispered Andrea. "Are you ready?"
"Oh yes, I'm so ready." I had never witnessed Jen getting fucked from this angle before; my view had always been from behind. Her hair was wild, cascading down over her face. Her boobs dangled down, covered in a sheen of sweat. Her rump was thrust up in the air, like a cat in heat. I realized that I thought she looked beautiful like that. Andrea seemed to savor the moment, caressing her sister possessively with one hand as she held the silicone phallus with the other. The rings in her pink erect nipples gleamed in the low light. Jet black pubic hair peeked out from beneath the strap-on harness. With one sure motion, she guided the artificial cock into Jennifer's pussy. Jen sighed, burying her face in the covers, letting her sister fuck her wide open pussy. I could actually hear the slurp of the dildo moving in and out of her vagina and the slap of their bodies clasping together. Andrea leaned forward, taking Jen's big full breasts in her little hands, hugging her sister tight as she fucked her.
It was too much for me. I didn't know what to think. I was too freaked out, turned on, jealous, and intrigued to deal. I carefully closed the door, leaving the amorous sisters to their lovemaking. My mind was reeling. I went to the kitchen and finished my beer, and then headed over to the school. Maybe that homework couldn't wait, after all.
The design building was left open all night for students working on projects. I made my way downstairs to the Design Studio, where my midterm project was waiting for me. I had planned on spending most of the weekend working on it. Spending tonight drafting would give me a good head start. The place would probably be deserted tonight; everybody else would have somewhere better to be than in a windowless concrete walled room, laboring under the fluorescents. As I walked the hall toward to studio however, I heard voices.
"Baby you got what Temple needs?"
"You know it Baby. I've been saving it all for you."
I walked softly to the open door of the design studio. Long ago, long before I had started school here, somebody had donated a couple ugly old couches to the design department. They stayed in the studio for the comfort and convenience of the students. I myself had slept there quite a few late nights. Sitting on one of the couches now was Nathan, a freshman who I hardly knew. He was tall, a beanpole; pale skinned and slightly effeminate. I didn't know him well, but I had kind of assumed that he was gay. Standing next to him was Temple, the late night cleaning lady. Temple was always very sweet and friendly to those of us who worked late in the studio. She was big, black, in her forties, with a wild head full of flaming red hair. I wouldn't say she was unattractive; I had simply never thought of her in those terms before.
As I stood in the doorway watching, I saw Nathan unzip and pull down his slacks, revealing the biggest penis I had ever seen, outside of porn. Mine isn't small; I would guess its average sized, or even a little larger. Nathan's tool looked to be a good three inches longer than mine. I was fascinated. He held it out invitingly, showing off his girth.
Temple, meanwhile, was peeling off her blouse and unsnapping her bra, revealing a pair of gigantic brown breasts with long erect nipples in the center of large dark aureole. She got down on her knees, resting her bosom on Nathan's thighs. She then did something that really threw me for a loop.
"Honey" she said "Let me tell you, I been looking forward to this all day!" She reached into her mouth, and took out her false teeth, setting her dentures carefully next to Nathan on the couch. Then she lowered her toothless mouth onto Nathan's huge cock.