Invisible Ch. 01

My name is John, and aside from having an IQ of 172, I lead a pretty normal life. I have a sister Carrie who is three years older, hot as hell and has been the subject of my fantasies for many, many years. She's got a great body and is physiotherapist in training.

In high school I excelled scholastically while she was the more popular one, changing boyfriends every couple of months. She was gorgeous, but bitter and always angry for some reason. I guess it had something to do with the fact that mom and dad had always attended to my needs first. It wasn't fair towards her, but it wasn't my fault. Although we were brother and sister, we rarely spoke at all and usually just avoided one another. She always seemed pissed at the world and could be mean and cruel for no reason.

Mom and dad had remodeled the basement for my special projects and it was where I would go whenever I wanted to try something, build something or take something apart. It was in that basement that I discovered an invisibility serum seven months ago. After testing it on some of my pet mice and developing a counteragent, I began using it myself. It worked like a charm and I could render myself invisible at will. The only practical catch was that I had to be naked for the serum to work, as my clothes were, off course, unaffected.

It didn't take long before I realized the possibilities of the combination: being naked and invisible. I began spying on my sister and jacking off while watching her take a shower or undress. The more time I spent watching her, the more it became clear that my sister had a strange fetish; whenever no one was around - or at least she thought no one was around - she would get into these risky, erotic situations by taking her clothes off or playing with herself at inappropriate times.

For instance, one of her favorite things was to go upstairs after dinner, take off her clothes and go into my parent's bedroom to diddle her clit. Sometimes she'd call it quits after a few minutes, sometimes she'd bring herself to a climax right there on the floor, or on the bed. Once or twice, I've even seen her bring her boyfriend along and fuck the shit out of him. She would also fuck him in her own room, with the door wide open.

This one time, about two weeks ago when dad was out and I was supposed to be down in the basement, she convinced her boyfriend to take an even greater risk. While mom was reading a magazine in the dining room, Carrie snuck down butt naked, with her boyfriend in tow in nothing but his boxers. In the kitchen, about five meters from where mom was sitting my sister got on her knees, sucked on his cock for like six solid minutes and took a massive blast to her face. Although she had the whole first floor at her disposal, she had chosen that specific location, simply for the risk of getting caught.

Needless to say, I really began obsessing over her. I had been lusting after her for a long time, but once I knew what a perverted freak she was, I wanted her even more. I started spending even more time spying on her, neglecting my other projects. All of my free time was now devoted to following my gorgeous sister around to see what other stunts she would pull.

Last weekend I followed her into her boyfriend's apartment, just a few blocks away from our house. I had expected to see her fuck his brain's out, but she didn't. Aside from a quick, clinical hand job when she arrived, she turned down all of his advances for the rest of the evening. She would let him grope and squeeze her but she wouldn't put out anymore. As a result, he had a massive boner for a big part of the evening.

When it was time to go, she insisted on walking home alone, although he'd proposed to accompany her. She gave him a long, wet, sloppy kiss and then left him hanging as she headed home. I followed her, walking just a few meters behind her. Suddenly, after walking for only forty seconds or so, she stopped and reached for the zipper of her skirt. After unzipping it, she hooked her thumbs behind the waistband and pulled her skirt down, along with her panties. As she stepped out of both items of clothing, I grabbed my hard dick and began jacking off. I gawked at my sister as she turned in place and faced every possible direction for a few seconds.

She unzipped her coat halfway down, pulled it down her shoulders and pulled her arms out, unbuttoned her blouse about halfway down, exposing her light blue bra, which she then pulled up, exposing her big, but firm tits without unclasping it. After tugging her hard nipples a few times, she picked up her skirt and panties and continued walking home, considerably slower than before. I couldn't believe what a fucking slut my sister was. Her boyfriend was probably whacking off, trying to get rid of the blue balls she'd given him, and here she was, with her tits and cunt on display for anyone lucky enough to pass by to see.

Considering the late hour, it was a calculated risk and for a while I thought she'd get away with her slutty performance, until I suddenly noticed a man in his early fifties walking his dog. He had turned the corner and was heading straight for us. As soon as he noticed her, he slowed down and looked around, confused.

"Are you okay miss?" he asked, stopping just before crossing her.

Carrie didn't stop and just said, "I'm fine, asshole!"

The guy looked at her gorgeous ass, bewildered, not knowing what to do. The risk she was taking, my god, this guy could have raped her right then and there, but she just walked on, her back towards him, not a care in the world. Luckily, we didn't run into anyone else and soon arrived home. I slithered in along with her and followed her into the living room, where she grabbed the remote of the TV and flicked it on and cranked up the volume to a pretty loud level. Then, she got onto the dining room table - dressed as she was - on her knees and began fingering herself, with just the light from the TV to illuminate the room.

It was as if she wanted to get caught; mom was a pretty solid sleeper, but dad was bound to wake up from all the noise. Still with one hand tugging her nipples and the other plunging three fingers up her soaking wet twat, she didn't seem to care. It was too much for me; I just sank to my knees in the middle of the living room, right in front of her and shot my big load on the carpet. As soon as my cum left my cock, it was visible again, so I left a pretty decent stain.

Before I could figure out how to clean it up, I heard dad coming down the stairs. I moved out of the way and watched, wondering what Carrie was going to do. Although she could probably hear dad coming down just like I did, she didn't react immediately and continued fingering herself for a few more seconds, clearly getting off on the impending danger. Then, suddenly, she jumped off the table and ran into the adjacent kitchen, barely a full second before dad barged into the living room, turning on the light in both the living room and the dining room. I moved to the far wall and watched as he grabbed the remote and switched off the TV. He then took a good look around both rooms, stepping in my sperm as he passed by - luckily he was wearing slippers.

"Damn TV," he grunted as he flicked off the lights and headed back upstairs.

Carrie came out of hiding and flicked on the dining room light again, got on her knees and fingered herself to a wonderful finish, three meters away from me. She bucked and trashed, convulsed and moaned as quietly as she could. I waited for her to leave and head up to her room, then made my way to the basement where I made myself visible again and turned in for the night.

Carrie had apparently scratched her itch because she didn't do anything sexually or depraved for two whole days.

Then, on the third night, after dinner, I went to the basement, made myself invisible and headed up the stairs to find my sister. True enough, I found her clothes scattered across the night hall, including her panties and bra, which told me that no matter where she was, she was stark naked. I found her in our parent's bedroom, with just the small night light on mom's side of the bed switched on. Carrie was on her knees playing with herself with mom's pillow stuffed between her legs.

Surely she wouldn't, I thought to myself. I could smell her twat from where I was standing. If she actually came on the bed, especially on the pillow, mom was bound to notice. But she didn't care and just fingered herself, spraying her scent all over the place. Rock hard and aching for a good release, I waited for her to climax before I chose to shoot my load onto the sheets, on dad's side. You know, to even things out a little bit, lol.

That's when things went south. Instead of lying down and relaxing for a few minutes as she usually did after any kind of climax, she hopped off the bed, not on her side, but flung herself towards my side. As a result, I couldn't avoid a collision and she bumped into me, toppling over onto me on the floor next to the bed.

"Auw, shit," I said out of reflex, realizing my cover was blown.

"John?" my sister shrieked as she jumped up and flicked on the light and looked for me.

As she couldn't see me, she began getting nervous and began to panic.

"Carrie, I'm invisible..." I whispered, trying to calm her down as I crawled away from her.

"Yeah, I figured that out by myself, but how... and what the hell were you doing here?"

Suddenly her eye caught the massive load I had just shot on the black sheets, bent over for a closer look and said, "My god, is this yours?"

"Yeah," I admitted.

"Were you spying on me, you little pervert?

"Are you seriously calling me a pervert, I've been watching you for weeks..."

"Weeks?" she repeated surprised.

"The thing I've seen you do... my god, I never knew you were such a perverted slut!"

"Yes, well," she stammered, "... I'm sure you were wanking off to each and every one of my perversions, weren't you?" she said, getting back on the defensive.

"Look, assuming we're not going to tell on one another, what do we do?" I asked.

"Well," she said, "You've got me at somewhat of a disadvantage, wouldn't you say."

She got dressed and accompanied me into the basement, where I took the counteragent, rendering myself visible again. For the first time since we were toddlers Carrie saw me naked.

After looking me up and down a few times, paying special attention to my half-flaccid cock, she asked, "So, what exactly did you see, you little perv?"

I began to sum up everything I had seen her do, including the flashing on the street thing.

"Look," she said, "I don't know why I do it, it's just a yearning I have that gets stronger if I don't give in to it... I like doing stuff when there's a risk of getting caught, the more dangerous and the more depraved the things I do are, the better my orgasm..."

Then there was silence.

"So, what now?" I asked, suddenly very aware of my nakedness as my cock began to rise.

"Well, the way I see it, we've got two possibilities... trying to forget this ever happened and going back to the way things were, in which case you have to promise never to spy on me again..."

"Or..." I asked, not liking option one.

"Or... we work together; between the two of us and your ability to become invisible, we could do some really twisted things..."

"You mean... do sexual things together?" I asked, baffled, "But you're my sister."

"That didn't really stop you from pumping your dick these past weeks, did it?" she replied with a smile. She took off her skirt and sweater, taking a step towards me in her underwear.

"What about your boyfriend?" I asked.

"Jeez, grow up John," she said as she squatted down in front of me, "Look, I am going to suck on your pole for a little while, and I'd like an answer by the time I am done, okay?"

Without waiting for a reply she engulfed my throbbing dick with her warm mouth and began blowing me like it was the most normal thing to do. Now, I must admit that all my reservations went out the door after seeing and feeling her bob her head up and down my shaft a couple of times.

This wasn't foreplay, or a loving blowjob, she wanted my spunk, as quickly as possible. And she worked hard for it. She brought me to a swift and powerful climax after just a few minutes. She grabbed my cock, aimed it at her red bra and jacked my sperm out of my balls, right on her bra and her cleavage.

"So, have you made a decision?" she asked as she looked up at me, extending her tongue and giving the tip of my cock a few more licks.

"Yes, fuck yes, I'll do it... I'll do whatever you want me to do," I blurted out.

"Good, we're going to have so much fun," she said. She picked up her sweater and skirt and made her way towards the basement stairs, clearly not planning on covering up. She opened the basement door and walked through the hallway, then headed up the stairs, probably to her room. Another risk, if mom or dad would have walked out in those five seconds, and seen her in her underwear, her chest covered in cum, coming out of the basement, we'd both be in a lot of trouble. It kinda gave me a kick. Yes, I believe she was right. We were going to have so much fun...

The next morning Carrie walked into my bedroom stark naked. The squeaking of the floor boards woke me up. As she walked up to the foot of the bed, I noticed she'd left my bedroom door wide open.

She pulled the sheet down and whispered, "Good morning brother," as she crawled onto the bed and hoovered her face over my morning erection, tenting my pajama boxers. There was no point in telling her she'd left the door open, I knew she'd done so on purpose. A quick look at my alarm clock told me we had four, maybe five minutes before dad's alarm went off, and he'd have to get ready for work. Carrie probably knew that too.

She slowly pulled my pajama boxers down and slid her hot, wet mouth over my cock and started sucking me slow and deep, gagging herself several times as she tried to swallow me all the way down. When we heard dad's alarm going off, she lifted her head up. For a moment, I thought she was going to hide or close the door, but she simply crawled up, put one of her legs on either side of me and guided my fat cock into her soaking wet snatch.

"Oh god," I whispered.

She started riding me, slow but hard, and mauled her tits with both hands, her head tilted back, clearly enjoying what she was doing. I was praying that dad had hit the snooze button. Unfortunately, not thirty seconds later, I heard the door to the master bedroom opening.

Carrie immediately leaned forward, getting completely on top of me, while she continued riding me, her pelvis moving up and down fast, and whispered, "Cum inside of me!"

As I heard dad approaching, I wondered how the hell I was ever going to cum faced with the prospect of getting caught in this incestuous scene, but as it turned out, it was a lot easier than I thought. We both turned our heads towards the open door and as we watched dad stumble by, still half asleep, heading for the toilet next to the bathroom, I climaxed and shot a big, juicy load deep into my sister's snatch. I knew better than to make any kind of noise, so I experienced my orgasm in complete silence.

As soon as we heard the door to the toilet open, Carrie sat back up and began riding me harder and faster than before, trying to get the most out of my still reasonably hard dick, and providing me with some additional pleasure.

When I was completely flaccid she dismounted me and got up from the bed.

"Not bad little brother, not bad at all."

She returned to her room adjacent to mine, again passing through the night hall stark naked where mom and/or dad could have easily seen her. I jumped up from the bed and closed the door as quietly as I could and sat on the edge of my bed contemplating what just happened.

About five minutes later, mom knocked on both my door and Carrie's door and said, "Rise and shine, breakfast in five." As she and dad headed downstairs, Carrie came out of her room and walked into the bathroom for a second before coming back to my room.

Wearing pajama shorts and a t-shirt, she said, "Here, put this on, under your pajama," as she threw me a black, lace worn bra and panties.

"Are you crazy?" I smiled, "I am not wearing your underwear!"

"They're not mine, they're mom's," she smiled, "Go ahead, smell 'm if you don't believe me."

"I don't know what mom's twat smells like," I said, getting defensive.

"Even if that were true," she said with a knowing smile, "Compare it to mine."

And with that, she pulled her shorts down and flaunted her freshly fucked twat.

"I don't care whose underwear it is, it's too dangerous... besides, I thought I was going to be invisible for all your little perversions."

"Oh not yet, brother," she said, her twat still exposed, "First we need to get to know each other's bodies, I need to know how hard your dick gets, how fast and how much you can cum, I need to know what turns you on and what doesn't... just consider this a grand rehearsal, we'll get to the real perversions soon enough. Now will you please put on mom's panties and bra, I promise you it'll be worth it!"

"Fine," I said as I put on the black panties, and then got some help from Carrie in putting on the bra, before putting on my pajama shirt and boxers. Carrie pulled hers back up, and down we went. By now I was half hard again. We said good morning and as I gave mom a kiss on the forehead, I felt my dick grow another inch as my cock head rubbed against her worn panties.

Uncomfortable, but horny as hell by now, I sat down and we ate breakfast as a family. Sis acted all innocent while I was having more trouble keeping a poker face, so I didn't really participate in the morning conversation. Aside from sharing what my college day looked like, I didn't say a word. When dad left for work about half an hour later and mom walked him to the garage, Carrie reached out and put her hand down my shorts, into mom's panties and around my hard dick. She pulled it out and started giving me a hand job right there. She didn't let go of my fat cock until mom was actually turning the corner into the kitchen, so that I didn't have time to put it back in my shorts.

I just sat there for a few minutes, with a giant cock under the breakfast table, hoping it would go down quickly.

Before it was even half down, Carrie got up and said, "Mom, you look like you could use a shoulder massage."

Mom smiled, "Oh hon, I am always in the market for one of your massages."

With that she walked up to mom, grabbed her shoulders from behind and gently started massaging them through mom's nighty.

Carrie said, "Ok, close your eyes and just relax," as she let go of the shoulders for a second, just long enough to quietly take off her t-shirt and push her pajama shorts down. After rubbing mom's shoulders stark naked for about ten seconds, she beckoned me over. I got up as quietly as I could and walked up behind her. I had a pretty good idea of what the crazy slut wanted me to do and by now, I was too horny to turn her down, so I carefully took off pajama shirt and boxers, then pulled mom's panties to the side to free up my fat cock and stroked it a couple of times.

Carrie looked back over her shoulders and smiled widely as she realized I had figured out what she wanted me to do. She pushed her naked ass back towards me and with surprisingly little effort I managed to slide my dick in between her ass cheeks and into her wet snatch. We both bit our tongue and didn't make a peep.

So there I was, dressed in mom's panties and bra, fucking my naked sister from behind, while she was giving mom a shoulder rub. It was too much for my inexperienced brain to comprehend and I blew my load after just eight or nine thrusts. I shuddered and convulsed and did my damnedest to hold my breath as I blew my load. As soon as my orgasm was over, I pulled my hard dick out of my sister's twat, picked up my boxers and shirt and literally stumbled out of the kitchen. I had to hold onto the wall and the door and everything else I came across not to fall over.