I was very young when I was adopted by a wonderful family and never felt that I was not their own child. Even though less than two years after adopting me, they had a child of their own, a daughter, Susan. We grew up as sisters in every way. However, by the time I was 18, little sis had changed from a loving play-friend into a brat.

She was 16, all leggy, her figure just beginning to blossom into what was clearly going to be a gorgeous girl. But so nosy, insulting, always borrowing my clothes without asking, using my make-up and perfume, helping herself to my jewelry; are all sisters that bratty or was it just mine? I wouldn't have minded if the clothing had even fitted her, but it didn't. I was a good four inches taller than her five foot, with a decent bust measurement of 34B so my clothes looked stupid on her. That still didn't stop her borrowing them.

One day, Mum and Dad were both out, I was feeling nicely wet and excited after some very sexy on-line chat with a girlfriend. Sue was in the garden, sunbathing and listening to what she called music, so I decided to take the opportunity for a relaxing half hour on my bed with my vibe. Believe me, if you have never had to share a bedroom with a bratty younger sister, you will not know how difficult it is to come without being disturbed.

I was well into it, lying naked on the bed, nipples hard and so sensitive, the warmth between my splayed open legs growing as I teased myself. I was running the tip of the vibrator along my smooth wet slit, just pushing the pussy lips aside while resisting the temptation to sink it deep into myself, knowing with each stroke that I was getting ever nearer to giving in, the need to come growing more compelling.

Just as I was about to do it, I noticed the bedroom door was slightly ajar, yet I felt sure I had closed it properly. Mmmm, who cared? My pussy was screaming to me, it was time, and I sank the vibe as deep as it could reach, twisting the control to full before starting to pump it in and out. I was so ready, it was only a minute or so of vibe-fucking before I screamed out, arching my back as I came. Oh God, it felt so good, hands and legs trembling and pussy twitching as I withdrew the vibe, feeling the wetness between my legs run onto my open thighs.

After cleaning myself off with tissues, I went to the door, finding nobody there of course. I closed the door from inside, then pulled at the handle but it stayed firmly shut. I threw on my jeans and top, then went downstairs, finding Sue sat in the kitchen in her bikini. Hmm, she was definitely more woman than girl. I forced my mind back to the reason I had come down.

"Sue, did you just come to the bedroom a few minutes ago?" I asked her.

"Why would I want to do that, with you in there?" she asked. "What were you doing in there anyway? I could hear you yelling from down here."

"I was minding my own business," I told her, "like you should do."

I left the room before she could start another argument. We kind of avoided each other the rest of the day. I knew Mum and Dad hated it when we argued. The truth is, so did I. I loved Sue, always had, but lately she seemed to go out  of her way to annoy me.

It was a few days later that it happened. I had not had the chance for another really good session, and only managed to come a couple of times in the bathroom, or in bed, using my fingers, after Sue was asleep, and always having to stop myself from making noise. But this evening, Mum and Dad were out together, Sue was at a friend's house, and I had the house to myself. Total bliss.

I went upstairs and stripped off. First, a shave, the hair was growing too much for my liking. I preferred to be totally smooth, made me that much more sensitive. I got into the shower, set the water to the temperature I liked, and lathered all over. I always enjoyed that gorgeous feeling when the rich scented bubbles slid between my legs, and the hot water made me tingle.

I watched my nipples become erect as I rubbed them with my sponge, then I lathered between my legs and shaved carefully, legs first, then the pussy, opening my legs wider to allow the hot water to hit directly where it had the most effect. By the time I had dried and powdered myself, I was almost ready to come there and then. 

I went into the bedroom with just the towel wrapped around me. Lying on my bed, I spread the towel out beneath me, and reached one hand down, stroking my fingers along my slit, two fingers slipping inside my wetness, and my thumb pressing against my clit. My other hand caressed my tits, squeezing my nipples hard before moving down to my pussy, then rubbing at my love button while the other hand slid fingers in and out, harder, faster, and I came so quickly, thrusting my bum off the bed as my juices flooded out.  

A noise from the doorway made me turn my head, and I saw Sue stood there, watching open-mouthed and wide-eyed. When she saw me look at her, she looked scared.

I called to her, "Sue, it's okay love, honest."

She still looked uncertain, but she came into the room, closing the door as she moved towards me.

"Sue, don't look so worried, it is fine," I told her. "Have you never done this to yourself?"

She crossed to the bed and I sat up, putting an arm around her shoulders.

"I thought you had to use the vibrator like the other day," she admitted, "was that what they mean by coming?"

"Yes, that was coming, and yes you can use a vibrator, but sometimes fingers are nicer. This is what Carla and I do when we can," I confessed to her, "You do know she is my girlfriend, don't you? And that we both prefer girls rather than boys?"

"Yes, of course I knew," she told me, "I am not stupid, you know. I am 16, not 6. How old were you when you started doing that?" she asked.

"About your age," I told her, "and a year later that I got my vibe."

"Can I see it?" she asked.

I took it from my bedside drawer. She examined it carefully, turning it on and feeling the buzz from it. Twisting the base to turn it up, then down again.

"Cool!" was her verdict, "Can I borrow it?"

"Okay, but you have to be careful, it might hurt at first," I warned her, "and for God's sake, don't let mum know. And clean it after you use it. This is only 'til the weekend, I will get you one of your own on Saturday if you want."

"Honest? Oh Marie, thank you," and she wrapped that beautiful girl/woman body around me.

After a few moments I felt her hands start to move slowly, one hand sliding down to hold my bottom, the other cupping one of my boobs. I pretended not to notice, even when her finger started stroking a nipple, but when she snuggled in to me and I felt her teeth on my neck, I knew I had to say something. I had to say something. The trouble was, it felt so good, and I could feel myself getting aroused.

At that moment, I heard the front door slam, as Mom and Dad came back.

When I went to bed later that night, I could hear noises coming from the bedroom before I opened the door. Usually, Sue was asleep by the time I came up, but tonight she was enjoying her new toy when I came into the room.

Lying on top of the duvet, a towel under her, she was clearly approaching a climax. I started undressing, watching her as she teased the vibe in and out of her tight little pussy, bottom bouncing as she hit the top, a muffled scream coming from her. She relaxed, watching me dreamily, while the trembling in her legs subsided.

I went over to her bed, taking the vibe from unresisting fingers.

"After watching that sexy climax, I think I might be needing this tonight myself," I told her.

She reached up to grab my neck, pulling me down with unexpected strength, and kissing me as I fell across her bed.

"Mmmm, thank you, Marie, it was wonderful," she stated.

"It is pretty clear that you came," I told her, still lying across her bed.

She gave a massive smile, holding up three fingers.

"Three times? You came three times?" I asked.

She nodded, happy and proud. More kisses, then a hand grabbing for my boobs. I sat up quickly.

"Sue, not a good idea," I told her. "What if Mum comes in to say "goodnight" or something?"

"Spoilsport," she muttered, "I was thinking of you when I was coming, you know,"

"Sue, darling Sue, we can't, you know that," I reasoned with her. "You are my sister."

"Step-sister," she corrected me, "and that makes it alright. I looked it up."

"And did it say Mum and Dad would be okay if they found out?" I asked.

"Okay, I get it," she conceded.

The argument had killed any urge to climax, so I used the bathroom and got to bed, saying "goodnight" to Sue as I lay down, but getting no reply.

I woke up from a disturbed sleep. It was still dark, so way before the alarm was due, and I was feeling so wet, so horny. No, not horny, I was coming. The covers on the bed were pulled back, my nightie pulled up high, my legs were wide apart, and Sue was next to me, naked, her fingers deep inside me, rubbing and teasing.

I no longer cared if it was right or wrong, I was coming and nothing was stopping that, not now. I just lay back and let it happen, trying to stifle my scream and being helped by Sue rolling on top of me and kissing me hard.

Once I could speak again, I put my mouth near Sue's ear.

"What the hell do you think you are you doing?" I demanded in a harsh whisper.

She kissed me again, putting a hand on my tit, teasing my nipple.

"Making you come," she whispered, "are you going to say you didn't enjoy it?"

"Of course, I did, silly," I admitted, "but I already told you it was wrong."

"Marie," she said quietly, rubbing her leg against my already sensitive pussy, "why is it wrong if nobody gets hurt, and if we both enjoy it?"

Between the questions for which I had no answers, and the rubbing leg against me making me aroused again, and having a sexy naked girl lying on me, I could not think of anything to say.

"I could always tie you down and help myself, you know," she told me. "I was so tempted to do that to you tonight, so I could play with you without you stopping me."

"Sue, that is not helping me, it just makes me more horny," I told her.

"Me too," she said, and moved, so her hand could stroke my wet slit.

She was lying on my left arm, with her right arm under my neck and holding my right hand. I tried to move my right hand to stop her stroking me, only to find I could not move it. When had she become so strong?

"You are getting me worked up again, Sue," I warned her.

"Good," she said, "that is the idea. It was fun, making you come. I want to do it again."

To be honest, I wanted her to do it again too. I was already feeling myself getting to that point where all that matters is coming. My legs were opening wider as her stroking grew more insistent. When she slid three fingers inside me and started pumping them in and out, I lost it, just thrusting up to meet her hand, and letting the climax wash over me.

She seemed pleased with the result of her actions.

"Mmm, that looked good," she whispered, nuzzling into my neck. "Again?"

"No, that was more than enough for me, thank you, and you should be in your own bed and asleep," I told her.

"I will go back to my own bed, but I need you to make me come first. Please?" she asked, "I never had someone else make me come, and I really want you to be my first."

"Okay, but you have to go to bed after that, promise?" I demanded.

"Okay, I promise," she agreed, "but only if you do me the way you do Carla."

"How do you mean?" I asked.

"You know. I saw you once, with your head down there, licking her," she told me.

"Whatever you want," I agreed.

I rolled her onto her back, opening her legs, and lying between them. My fingers traced a path along her wet slit, making her squirm delightfully. She was so sensitive, this was not going to take long.

I gripped her hips, pulling her down the bed towards me, and started teasing her, my tongue probing inside her tight pussy, and already she was gripping the sheets. I slowed down, just lightly running my tongue along  her slit, tasting the juices as she wriggled, trying to press harder into my mouth.

When she started moaning softly, I knew she was ready. I started to lick and flick that gorgeous clit, pulling her hard onto my tongue, and she went right over the top, muffling her screams in the pillow as she came. She was still shaking when she dragged me to her, kissing me wildly.

"Oh God, thank you, Marie, thank you. That was like nothing I ever felt," she babbled.

I held her in my arms while she calmed down, and started breathing more gently.

"Okay, ready for your own bed now?" I asked, "and no more wandering. I need some sleep."

"Spoilsport," she moaned, "I would rather do this than sleep."

She looked at me, my face clearly showing my annoyance.

"Alright, I am going," she announced, "anyway, at least now you know you don't have to do it to yourself anymore. Hmm, next time I think I will tie you down before I wake you."

Once she was safely in bed, I tidied my sheets and settled down to sleep. My last thought was, "Tie me down before waking me? She is just joking. Isn't she?"