A Little Help From Her Friends

The display you just witnessed has already branded itself into your mind and you just can't seem to shake it. You go upstairs and take a trip to the bathroom, sitting on the closed toilet seat and pulling down your trousers so you can masturbate in peace. Strangely, you find it's not your sister's nakedness that's turned you on so, it's those panties she was wearing. The ratty grey undies with the barely-elasticated waistband; quite the unexpected turn-on. There had been a point where it fell away from her front, just enough to give a hint of the naked skin below and beneath, and it set your imagination running wild even before she'd taken them off. There had been a hole, too, miniscule, in their seat, giving nothing but a small window into her ass crack. Christ, you think, even as you go to work stroking, moving your foreskin back and forward over the bell-shaped head to the thought of your sister. She was poking fun, ripping mercilessly into your ENF fetish, but even so that high, girly voice she'd put on and the panicked refrains about her, 'boo-bees' get you going just like the real thing, if not slightly better. There was something there, a disturbing nugget of...enjoyment? A twisted kind of pleasure you felt at being degraded by a girl both naked and unafraid of being so, it's the kind of thing you prefer not to think about, the kind of thing you'd very much like to bury and forget. Your thoughts drift back toward the firm pair of tits and high, flatteringly-shaped booty it turns out your sister's been packing all this time. It briefly makes you think of a time not so long ago when she forgot to lock the bathroom door while showering, you'd walked in on her with her back to you; the warm, steamy room had been filled with the sound of loud, wet schlicking and her butt pressed flat against the shower's glass wall, cheeks vaccum-sealed into place and wobbling gently up and down in time with her movements, making quiet squidging sounds. It had all brought thoroughly unclean thoughts to the forefront of your mind. You can sense you're about to bust when you hear a quiet click at the closed door. Unsatisfying as it is, your curiosity is sufficiently piqued that you let the steadily-building pressure at the base of your shaft go unreleased, stuffing your still-hard cock back into your boxers while you get back to your feet and shuffle over to to it.

You try the handle, but it's locked in place and clicks uselessly at your touch. Outside, you hear muffled, girlish giggling and faint, faint footsteps. "What are you doing out there? Hey! What's going on?" Another attempt at the door yields no results, and you flop back down on the seat in frustration. Your sister's up to something, you just know it; chances are she'll let you out when she's good and ready, though exactly what that'll look like makes you more than a little uncomfortable. After giving it a good twenty minutes, you look up at the sound of another loud click at the bathroom's door. You're on your feet instantly, and sure enough the door opens on your first try, and you find yourself stepping out onto the upstairs landing, where you catch a bouncing tangle of dark hair and the unmistakable sight of a slim, shapely back disappearing down the stairs. "Hey! What are you up to?" You call after the decidedly feminine figure, before starting along the landing and downstairs after her.

First, you investigate the living room again, expecting to find your sister up to some new, ridiculous game. To your surprise, when you round the corner and walk through the open doorway, it's not your sister that greets you, but her long-time friend, Christie. Christie's a buxom blonde, and right now her great heaving breasts are free and unrestrained. Her nipples are huge—big wide rings, bronzed like the tan that covers much of her body, save for the pale strips of her tan-lines, running along and around her crotch. She sits slumped far into her part of the sofa, her legs open wide, labia spread open, looking for all the world like little butterfly wings. Between them you see everything, the thin ruffles of her inner lips, the small wet oval of her opening, and, thanks to how low she's sitting on the sofa, the tiny creased hoop of her anus, all taut and sweet, and several shades lighter than the rest of her. You stare, hypnotised by her body, and she gives you a warm smile. "Hey, you." She wriggles cutely further into the back of the sofa, asshole winking subtly as she does, and she follows up by batting her eyelashes at you in a way that makes your heart melt and your cock solidify. "H-h...hey...hi..." You stammer, your face reddening under her scrutiny. Christie makes a concerned face, "What's wrong? Cat got your tongue?"
"You...you're not..."
"Wearing any clothes?" She cocks her head, long tresses falling over her shoulder with the motion. "No. Guess I'm not. That a problem?" Her last few words are muffled by a practiced, sleepy yawn, and with it comes a high, croaky moan from deep in the back of her throat. "What's wrong with being naked, anyhow?" She rubs her eyes, almost closing them. "Especially when you're pretty..." They snap open again, and she looks at you questioningly. "You do think I'm pretty, don't you?" She asks, running a finger far down by the spot where her asshole sits, the little starfish shivering where she traces a small circle around its circumference.
"I...I..." You can't do this, it's too much, you feel your prick prodding the button on the front of your boxers, and a colour rising high on your cheeks, so you spin on your heels and leave the room, going back down to the kitchen, hoping all the while that Christie won't follow you and that you'll get a moment to be alone with your thoughts.

You're right about Christie, dead wrong about being alone. The first thing you see as you walk into the kitchen is a pair of pale, modestly-sized but pleasingly perky globes, every inch of them decorated with light brown freckles. Furthermore, she's standing on a stool to better reach the sink—she'd always been the shortest girl you know—which gives you a tantalising glimpse at the protruding mound of her pussy lips, peeking shyly out from the bottom of her, well, bottom, a few scraggly tufts of orange pube gathered around them. When you finally manage to tear your gaze away from that image, you look up and see a blaze of bright red hair cascading down their owner's back. "Penny?" You say, struggling to pick your jaw up off the floor. Another of your sister's oldest and dearest friends, and one you've long nursed a crush for. You'd always wondered what was hiding under the baggy cardigans and long skirts she's always habitually worn, and now you know. Penny turns her upper body to get a look at you, and you see she's wearing bright yellow rubber gloves—the only thing she's wearing, as a point of fact. "Hey, big boy!" She gives you a pleasant smile. "Come to help me out?"
Your reply is an incoherent stutter. Penny giggles, her body shaking such that the freckled globes of her buttocks jiggle. "Wow, you've got it bad." She remarks.
"G-g-got...got what?"
"Pretty girl in her birthday suit and you just don't know what to do with yourself. Your sister was right; is it true you prefer your ladies red-faced and stammering the way you are now?"
"I...she told...?"
"Oh, yes. She tells us everything. Did you pull yourself off to her, by the way?"
Your Adam's Apple bobs when you swallow. "How..."
"How did I know your sister stripped down and showed herself off to make a point? And how did I know you went upstairs afterwards and touched your willy until it just about exploded at the thought of it?" Penny flutters her eyelashes innocently. "Little birdie told me, of course. Now are you going to help me out here or not?"
"Help you...out?" You echo, brow furrowing in confusion. "Why...why are you even here?" You're trying to distract both her and yourself from the absolute rager of an erection you're currently sporting; to your surprise and no small amount of shame, you're sure that your 'willy' twitched and rose just a bit higher at the mention of what you did to it in that bathroom. How could Penny know? How could she know you wrapped your fingers around a shaft, rock-hard and throbbing with heat, and stroked yourself silly to the memory of your naked, blissfully unashamed sister, images of her proud pink pussy and buoyant breasts flashing through your mind as you jerked and jerked, feeling the cum rising out of your balls and up your big, stiff rod until you were so rudely interrupted.
Penny shakes her head as if you've just said something stupid. "Someone's gotta do the difficult jobs around here when your parents are away, now don't they? Granted, Daddy always said I should never put on gloves or an apron just because a man won't do it himself, but then I'm not wearing an apron, and besides, these are special circumstances." She giggles again, tugging on the bottom of one of her gloves with the other until the rubber starts to stretch, then releasing it with a loud snap. "So what'll it be, big boy?"
You barely understand the question, maybe if you stay here a while and count the freckles on Penny's bare bottom it'll come to you.

[Author's Note: I always enjoy and appreciate feedback in terms of what's working and what isn't, so please feel free to like and/or leave comments!]