Bane of my existence

I loved being home for the summer. At least at the beginning of the vacation, while my parents were both still at work and Casey still had another week left of school.

I had the house to myself, which I celebrated, as you might expect, by stripping naked and walking around the house with my cock and balls swinging freely in the crisp morning air.

I strolled around the house, making myself breakfast and watching a bit of TV, occasionally playing with my semi-erect member. It was a very pleasant way to spend a morning and I can highly recommend it.

In truth though, I was actually trying to put something off. I was trying to distract myself from an itch in the back of my mind. I kept pushing it away or trying to ignore it, but it grew more and more insistent. I knew that I was kidding myself that I could hold back from the painful urge building inside of me. I already knew where my little naked walk would eventually lead me.

My sister's room was down the hall from mine, and I had avoided the place ever since she hit her teens and developed something of a nasty streak.

Casey was a senior now, recently turned eighteen, and I would be lying if I said I hadn't begun to notice the way her flourishing body had begun first to fill, and then overfill her clothing.

It was hardly my fault that I could not stop staring at her. She always seemed to be close to spilling out of her clothes. Every corner I rounded in the house she was there, bending over, showing me a sliver of plump ass cheek in her tight little gym shorts, or far too much butt crack to be considered decent when she squatted to get a book out of her school bag. If she dressed that way for school every day, I am surprised that she has not yet been suspended.

Cautiously I entered her room. For some reason this felt riskier than parading around the rest of the house naked. Almost thoughtlessly I found my hand resting atop the laundry hamper by her door.

I wouldn't have done anything really, but they were just sitting there, right on top of the pile. A pair of soft cotton panties. The panties were a pale pink, the very color I imagined her nipples to be. They were light in my hand, barely there, a tiny scrap of a thong that would not cover very much at all.

I lifted them gingerly from the laundry basket, rubbing the thin material between the pad of my thumb and my forefinger. I imagined I could still feel heat where her pussy had snuggled up against this soft material.

I knew what I was doing was bad. But really I blame her. Since I had come home from college and found her metamorphosed from a chubby teenager into a stunning curvy woman, how I saw her in my mind had shifted dramatically. The way she spoke, dressed and acted seemed deliberately intended to provoke a response in me.

I gave the panties a tentative sniff. They smelled like her. At least, they smelled of the citrus perfume she wore. But there was also a certain musky tang I recognized. It was the scent of her sex. Alike, and yet different from girls I had gone down on before.

My exposed, semi-hard dick twitched and swayed from side to side.

I took a last, careful look around Casey's room. No one was there. No one would be home until this afternoon.

Carefully, I stretched the panties and pulled them over my head. I nestled my nose into the part where her crotch would have rested and let the elastic snap tight around my head. The holes where her legs went made a perfect, if odd-looking, mask through which I could see.

I wouldn't say I was proud of what I was doing. I purposefully avoided looking directly at myself in the mirror. But I could not fight the growing urge I had to be close to my little sister. This way, at least, was relatively safe and harmless.

I took a deep breath in through my nose. Her scent filled me. My dick's response was instantaneous, elongating and fattening like a feeding leech before my eyes.

Though my cock was begging for it, I didn't touch myself just yet. That was a special reward for a bit later. Instead, I perused her room, fingering her collections of knickknacks, most of which were from her recent childish past.

There were some signs of her newly sprung adulthood. Some new books and posters, as well as pictures on the wall, but a lot was unchanged from when she had been my bratty teenage sister.

Actually, she was still my bratty teenage sister. But having the number "eighteen" attached to her changed the way I thought about her a lot.

One picture in particular caught my attention. It had its corner wedged into the frame of her mirror. Ignoring the reflection of the naked man with the pink panties over his face, I peered closer. It was of her and her friend Jordan. They had their arms around each other and both were in swimsuits. Jordan was in a green bikini, which displayed her flat stretch of slimly muscled belly. Casey had her more womanly body encased in a blue one-piece. Its plunging neckline, and the high angle from which the selfie was taken, meant that the view into Casey's ample cleavage was deep and enticing.

Using only the flat of my hand I began to stroke the top of my dick. It wagged in appreciation.

Of course, I knew it was wrong to jerk off to my sister, but who would know? Her body had developed into the sexiest I had ever seen, thick in the bust and backside, both of which flared out dramatically from her tiny waist.

It was the type of figure, almost absurd in its cartoonish proportions, no woman could maintain past the first flush of womanhood. Eventually metabolism, age, and gravity would catch up with her, as it did with everyone. So it felt only right that I should appreciate it now, like a fragile blossom before a storm.

I wrapped my hand around my length and was beginning an easy stroke. It was still early in the act, I intended to prolong it as long as I could, but I checked Casey's desk to make sure she had some tissues on hand. I did not want to have to clean up a big mess afterward.

That was when I heard the soft rasp of someone clearing their throat.

Instinctively I spun, dick still in hand, panties over my face.

My sister was leaning casually against the jamb of her door, her cellphone in one hand, its camera pointed directly at me.

"What the fuck are you doing?!" I squeaked.

She gave me a partially-amused frown before saying, "You know, I was just about to ask you the same question."

"Fuck!" My mind raced, desperate to think of some kind of excuse, any excuse to explain away this situation. But every time I dug, right down to the bottom of the barrel, desperately trying to pull up an excuse, the same message kept being dredged up: "Fuck! Fuck! Fuck!"

"Pink is a good color on you," she mused dryly, her attention returning to her phone screen.

When I failed to answer again, the sound of my beating heart seeming to drown out all other thought patterns, she continued, "Care to explain the headdress? It looks familiar, but I can't quite place it. Is it cultural in some way?"

My mind ran in a loop of self-defeating terror.

"It couldn't possibly be your little sister's panties. That would be perverse."

"Um," I fumbled with the words, before finally managing "I'm working on my Bane impersonation?"

When she looked unconvinced I added in a gruff voice with its signature squeak, "You merely adopted the dark. I was born in it."

An uncanny impression, even if I say so myself.

"Maybe it would be more convincing if Bane walked around naked, with his erection in one hand." She thought for a moment and then added, "Actually, that is a movie I might pay to see."

Realizing she was right I yanked my hand off my shaft like it had been burned. Strangely my erection had not lessened during this entire catastrophe. If anything it seemed to flare painfully under her scrutiny.

"You're not meant to be home," I rounded on her.

"You're not meant to be jerking off with your sister's panties over her face, but life is full of surprises."

"I mean, you're supposed to be in school."

"Meh," she shrugged, "School is boring. Especially the last week before vacation. I bunked out after morning register. Jordan is covering for me. She'll tell them I'm in the bathroom or doing something for some other teacher. I do it all the time. This," she nodded in my direction, "This is far more interesting. I am so glad I came home early."

"What are you going to do?" I asked, unable to hide the thread of desperation that was winding itself around my voice.

"You know, it's kind of hard to decide. There are so many things I could do, especially now that I have this video." she tapped her phone with the long nail of one finger.

The creeping terror inside me rose. Instinctively I made a move towards her, intending to grab the phone but she forestalled me by holding out the flat of her palm.

"Uh, uh, uh," She tutted, "This is already on the cloud. You can't touch it. One more step and I post this on the family group chat."

"You wouldn't!"

She didn't say anything, but look she gave carried the clear message, "Wouldn't I?"

"It would kill grandma!"

"Hey, you're the one who taught her to text."

"Delete it. Please delete it!"

"Hold on, I'm going to need some things first."

"Like what?" I was too frantic to escape the situation to worry about why she was taking this all in so easily. Surely your older brother jerking off to a picture of you warranted a little less calm detachment.

Casey was as cool as ever though, as she said, "Like, I want to borrow your car this Friday."

"Never!"

She shook her head in mock sadness and, looking down at the phone, said "Dear grandma, Edward wanted you to see this video. Look closely and you can see that the panties he has over his face belong to me, his blood relative." Tapping her lip with one finger she added, "Hmm, I don't think they have an emoji to represent incest."

"Fine." I growled, "What else?" There always was something else with my sister.

"Your phone."

"Fuck off."

"I'm not getting an upgrade for another year and yours is so shiny and new. Plus," she added as she slid a finger up the side of her phone, "This one is now full of dirty videos."

"Anything else?" I asked through grinding teeth.

"I'll need time to think it over. There is really so much I can do with this now."

She cocked her head to one side. I instinctively tried to cover myself with my hands as her focus dropped down to my still erect penis.

"But, why don't you start by carrying on where you left off."

"What?!" I blurted.

"You heard me. Take that big 'ol dick in your hands and start beating it."

"Are you fucking with me?"

"Nope, and let's make it interesting. You have to jerk yourself off, but you are not allowed to come. If you can do that I'll consider letting you delete the video."

"And if I do come?"

"Then this finds its way onto the internet."

"You have to be kidding me."

"Nope. I am quite serious. If you come I am going to post this everywhere. Seriously. There will be tribes in Amazon rainforest who have not had contact with the outside world in centuries who will be talking about the guy jerking off with his sister's panties over his face."

"Fuck you!"

"You wish," she said and then added with an eyebrow quirked in the direction of my still swollen cock, "Apparently."

"Why are you doing this?" I asked, a pleading tone entering my voice.

"I'm bored, remember? And making you suffer amuses me. And this is just too good. I mean who would have thought my dickhead brother has the hots for his little sister?"

"I don't. I..." I tried to argue back, but it is hard to make a point when half your face is covered by your accuser's pink underwear.

As I lifted my hand to remove the garment my sister tutted and waved a finger at me. She was still looking at her phone, but I stopped what I was doing.

"Wait, are you still recording me?!!"

"Yup, the first one was so good I decided to make a sequel. You had better start listening if you don't want these to see wide release."

In frustration I let my hand fall to try and cover my crotch and then I glared at her with as much venom as I could muster.

"Uh, uh uh." She motioned to the hand. "Come one, big boy. Show me what you got."

I knew my sister well enough to realize that she was not about to relent. Added to that was a certain kind of thrill I got each time she peeked over the top of her phone at my bare cock.

I mouthed the words "Fuck you" directly into the camera, but I capitulated nevertheless and wrapped my hand around my cock once more. It throbbed painfully.

I stood there for a long moment until my sister finally looked up into my eyes with an implicit challenge and mimed her hand jerking an imagined cock.

Slowly, and making sure she saw the protest in my eyes, I took a long pull on my hard dick.

Casey smirked in such a way that it made the dimple on her left cheek appear. It sent a warm tingle through me that I suppressed beneath a mask of anger.

"That's it, Eddy boy. Beat that meat. Flog that dolphin," As she spoke she moved into the room, keeping the camera trained on me. Not taking her eyes off me, she found the edge of the bed with one trailing hand and sat her generous rump down. She was close enough to me now that, if she leaned forward and stretched out, she could touch my cock.

Her camera was directed right at the head of my dick.

I maintained my look of stoic detachment while I slowly massaged my cock. It would not have been enough to get me stimulated under normal circumstances and, I figured, that if I did this for a while she would get bored and let me go. Whether she would let me get my hands on the video was another matter. But for some reason, the sheer wrongness of having my little sister watch me touch myself, completely naked, in broad daylight and in her bedroom was doing something strange to me. Already I could feel an intensely pleasurable buzzing sphere of energy just behind my dangling testicles which warned of an approaching climax.

I shifted uncomfortably on my feet, trying to reset the detonation sequence which had already started. When this didn't work I slowed down even further.

"That's not good enough," She observed in a sing-song voice.

"You said I had to jerk off you didn't say how fast," I retorted.

"Okay then, but if you are going to cheat, then so am I."

"What do you mean?"

But she did not respond verbally. Instead, I watched in fascinated horror as she hooked a finger into the deep vee of her top and gave the material a little tug. I tried hard to look away, but the jiggling of those plump tits and the increase in her already scandalous cleavage was maddening. On my next downstroke, I had to pause and pinch the base of my cock to try and calm myself down.

"Aw, what's the matter?" She asked in a sarcastic pout, "You gonna come already? What are mom and dad going to say after they see this? Especially if you kill Grandma."

"I'm not going to kill Grandma!" I said angrily. I could see this level of control was making her giddy. She was enjoying this far too much and I had to bring myself back down. I could not give her victory, no matter how much my cock was begging me to unload itself all over the indecently exposed skin of her breasts.

I sucked in a deep breath and relaxed and flexed the muscles beneath my perineum. This gave me some level of control back. Added to this was the list of every Star Wars character I knew, which I had begun reciting in my head to try and distract my mind. Slowly but surely I began to push back my rising orgasm.

As I felt my control return it was my turn to smirk down at my little sister as I stroked my cock lazily while enjoying her incredible cleavage. Maybe this wasn't so bad. I just had to keep going exactly like this and I would win. Not only that but I would have a rich tapestry of new masturbatory material I could draw on later when I was on my own again.

I saw the annoyance flicker across Casey's adorable heart-shaped face and it only made me feel more confident that I could wait her out.

I should have known Casey would not let that happen.

I saw her tense the muscles in her shapely jaw and narrow her eyes in determination. When she looked up at me again her expression had changed to a pathetic wide-eyed innocence that I knew was total crap. It didn't stop it from being incredibly hot.

She shifted on the bed as if suddenly in discomfort before asking, "Do you mind if I take off my bra?" She asked in a sweet little voice that I only heard from her when she wanted my dad to buy her something, "It's really tight and I could do with a break."

It always worked on him. I was determined it would not work on me.

"Fuck off," I hissed through clenched teeth.

"It's just that they've grown so big lately and mom hasn't yet taken me to buy new bras, like she promised. I'm sure you won't mind if I just take this one-off. It is my room after all." As she spoke she reached behind her and under her shirt.

I saw the self-satisfied grin on her face just before I heard the crack of her bra clasp being released.

I let out an involuntary groan as her heavy breasts sank visibly after being released from their constricting bonds.

Casey pretended to ignore me then as she performed a complicated maneuver under her shirt which allowed her to slip the straps of her bra off without removing her shirt. With a final tug and a flourish, she drew out a white padded bra with pink lace trim at the edges.

She held it up in front of my face. Her expression was impassive, but I saw the crinkle of amusement in her eyes as my hips gave an involuntary jerk forward.

She dropped the bra on the bed and leaned back on her hands, pushing out her impressive chest.

I swore softly, I could now see her high, erect nipples poking through the material of her thin top.

But I kept myself together, just. This was about more than just the video, the car or the phone now. I could feel we had entered some sort of silent battle of wills. There was no way my bratty little sister would win.

For a time she pretended not to notice her brother stroking his cock at the end of her bed. She looked around the room, puffed out her cheeks, crossed and recrossed her legs. All the while she made certain that every movement was transferred to her tits, which jogged and bobbed enthusiastically with even the slightest twitch.

I gnawed at the inside of my cheek, hoping this was a sign that she was getting bored.

When she looked back at me she did indeed appear to be bored at first, but then something caught her attention. Her expression lit up and she shifted her weight forward.

"Oh dear, big brother, looks like its soon going to be all over," she crowed, as she stared directly at the purpling tip of my dick.

I looked down to see what she meant and saw the clear bead of liquid that had formed in the pit of my urethra.

"Hmph, It's just precome," I grunted. "I can do this all day."

"Yeah, Ed, we all already know you're a jerk off," she answered, but I could see this presented a fresh challenge to her. Grim determination set itself into her features and she finally turned off her phone's camera and set the device to one side of her.

Under the guise of increased scrutiny, she leaned forward. As she did so her massive tits threatened to spill out of her top. Any pretense that this might be unintentional was ruined by the arm she had slipped under her breasts to lift and push them outwards.

She stared at the painful-looking inflammation of my glans before saying, "I don't know, it looks ready to pop."

With her beautiful face right in front of it, I had to really fight back the urge to prove her right. I was so tempted to disgorge the entire contents of my testicles all over her smug little face.

Clearly sensing she had regained the upper hand she looked up at me again. Through large, liquid eyes,and cooed, "You want to come for your little sister?"