It all started when I began taking photos of our touch rugby team. It was a mixed team and my sisters, Caitlyn, Lauren and I had been playing for years.

Caitlyn was the older of the two; she had just had a birthday last month. She was a very shy and petite girl at only 4ft 10 and very slim build, which contrasted nicely with her B-cup boobs and long brunette hair. Lauren on the other hand was very opinionated and constantly getting in trouble at school. She was 1 ½ years younger, but already taller than Caitlyn, but she had only just started to fill out in the chest department and hardly ever bothered with a bra, which was made very obvious by her constantly hard nipples.

Our mum had asked me to take some photos of the team as we played, so whenever I wasn’t on the field I would be taking pics with my phone of everyone running around. I was on the side-line, when Lauren came off and stuck her tongue out at me, of course I immediately squirted her with my water bottle, causing her to squeal and jump backwards to get away. But I got her pretty good anyway.

There she was with a rather wet shirt, nipples poking out as always and she hitched up her tights a bit higher producing a very noticeable little camel toe. I always thought my sisters were pretty and I had fantasized about them a bit, what teenage guy hadn’t thought about his sisters? I immediately zoomed in and took a photo. She gave me a funny look and just turned away and watched the game, so I took another shot of her ass. It was at that point that I decided since I’m taking all these pics anyway; why not try to get a few shots of my sisters great asses. Just the thought of it sent a rush of blood to my dick. Unfortunately I didn’t get any more opportunities that day.

Once we got home there was the inevitable rush for the shower, the girls shared a bedroom and we had a bathroom that connected our bedrooms. I wasn’t worried I just wanted to get on my computer and see how the pics of Lauren had come out. I could hear the girls giggling as they started the shower and I plugged in my phone. The first photo was okay, but the shadow and black tights didn’t show a lot, but the ass shot was great. She had the most wonderful little ass, I could only imagine how it would feel to touch it and squeeze those cheeks between my hands.

My cock was getting really hard and I decided to try and get a quick wank in before I had a shower. I checked my bedroom door was locked and brought up a favourite sex story from the net and kept the pic of Lauren’s ass on the other side of the screen and slowly started to stroke my dick.

I was getting close when I heard the water shut off and Lauren yell out “Caitlyn! Can you bring me a towel?” I paused for a moment, imagining her slender body under the water.

“Caitlyn? Are you there? Caitlyn?!” Lauren yelled again.

I guess Caitlyn must have gone downstairs or something, because the next thing she said was “Alex? Can you pass me a towel please? I forgot to get one.”

My heart was hammering as I thought this was the perfect opportunity to try and get a real look at her. I know she was only young, but I had only seen pictures of naked women, never the real thing. I grabbed my towel and opened the door, the room was pretty steamy but I could still see her standing in the shower cubicle behind the glass, with one hand over her pussy and the other across her small breasts.

If I hadn’t been close to cumming before I was now. The sight of all that gleaming skin barely covered by her hands had me right on the edge. Thank god for the towel covering what must have been a very obvious bulge in my shorts. I just stood there transfixed by her beauty, until I was jolted back to reality when she said “take a picture why don’t you! Quit staring you jerk!”

I quickly said “I’m sorry” and threw the towel across the room and scurried back into my room and sat back down. WOW, she was hot, I thought. I pulled my dick out again and started stroking myself, a few moments later I blew a huge load all over my chest. Shit, I thought, my t-shirt was covered in my cum. Mum is certainly going to notice that when she does the washing.

I grabbed an old shirt and pulled that on, and then I heard the shower start up again. That must be Caitlyn I thought, then I had an idea, Lauren had said take a picture, so why shouldn’t I?

If I’m really careful, maybe I can open the door and Caitlyn won’t notice me. When you’re facing the shower her back would be to my door, I could try and get some pictures of her naked! She is definitely the hotter of the two; she looks just like Michelle Trachtenberg back when she was on Buffy. She usually covers herself up quite a bit and she’s really shy, but there was no denying how beautiful she was and here was my chance to see for myself. But did I have the courage? The trouble I would be in if I got caught, was barely worth mentioning. Our parents were quite cool, but they certainly wouldn’t be happy catching there son perving on his own sisters.

My little head made the decision for me quite easily. My hormones were racing, my dick was hard again just thinking about it and I decided to go for it. I could hear the water splashing so I knew Caitlyn was in the shower already. I tiptoed over to the door, why I don’t know, since there was no way she could hear me but I wasn’t thinking very clearly anyway. I knelt down with my phone on video mode and slowly turned the handle, the rush of water instantly got louder and I inched the door open. I didn’t hear any screams of indignation so I stuck my head thru the gap.

I couldn’t believe my eyes, there was my beautiful little sister standing under the spray rubbing shampoo into her hair. That perfect little heart shaped ass was directly in front of me and as she moved around I caught a side view of her cone shaped tits. I guess they were about a B-cup capped with puffy little pink nipples sticking out. I stared for a moment before remembering the phone in my sweaty hand. I started recording and just stared as she started to rinse her hair, still with her back to me thankfully, but at that point I don’t think I could have moved even if she had looked right at me. Once she had finished with her hair she squirted some shower gel onto a sponge and started soaping up her body, it was getting quite steamy and was becoming hard to see but I noticed she seemed to be paying a lot of attention to her pussy which I still hadn’t seen.

Our shower had one of those detachable nozzles, she reached up and grabbed it and rinsed all the soap suds off. Then she put one foot up on a ledge and started rubbing the nozzle on her pussy. I couldn’t believe it, my sweet, shy little sister was masturbating in the shower! And I was getting it on film! My cock was fit to burst and I was almost cumming in my pants without even touching myself and I didn’t even have that clear a view. But it was more than enough for me.

Suddenly she turned around and my heart stopped, I’m caught! The thought flashed thru my mind but she didn’t seem to see me. She sat down with one leg up on the ledge with her and the other straight out in front of her. I had a great, if cloudy, view of her pussy. I couldn’t see any hair, where was her bush? Does she shave I wondered? That thought was quickly driven from my mind as she brought the nozzle down and started rubbing it up and down her pussy while her other hand pinched and pulled at her nipples.

This is incredible, I’ve died and gone to heaven, life surely can’t get much better than this and I’ve got it recorded to relive it every day. I could hear her moaning and it seemed to me she must be getting pretty close to cumming herself. She was saying something over and over again, but I couldn’t quite hear her over the sound of running water. Suddenly she arched her back and pulled really hard at one nipple and cried out something that completely shocked and surprised me.

“LAUREN!”

What? She was crying out our sister’s name as she was cumming? The sight and shock was too much for me, I came hard in my pants firing jet after jet of cum into my shorts. I crouched there panting as I watched Caitlyn shake as small spasms rocked her body. She just sat there for a minute with a dreamy smile on her face and then she stood up, SHIT, I thought I can’t let her see me. I backed up and leant back against the door, closing it and trying to catch my breath after the show my sister had just put on for me and she didn’t even know it.

I sat back down at my desk and felt the rather sticky mess I had made in my pants. Damn, I had cum twice in less than twenty minutes and my dick was half hard again just thinking about what I had seen. I plugged my phone in and copied the video to my computer and checked it. The quality wasn’t great, due to the angle and the steam, but it was still pretty awesome, I could easily see Caitlyn in all her glory and at the end I could clearly hear her say Lauren’s name.

I grinned to myself, my sister has the hots for Lauren, surely I can use this to my advantage, but how?

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