Sister in the Shower

** Hi there! This is my first story that I'm posting on here, but hopefully not my last :) Let me know what you think. **

I got out of the car and headed inside the lake front cabin behind the others. Setting down my bags in the living room, I watched my step siblings, Laura and Derek, poking fun at each other. Laura is the same age as me, 20 years old, but she's more of a prude and keeps her blonde hair short and straight. I'm half Mexican, so my long, dark brown hair runs down my back with bouncy curls. Derek is younger than us having just turned 18. He's a tall, shy boy and doesn't talk much to me, but is close with his sister.

"All right everyone, go find your bedrooms," my mom, Samantha, yells at us from the car.

"Save the biggest bedroom for the adults!" their dad, Matt, follows alongside my mom.

Derek ran up the stairs and I followed behind him. The room was small and quaint, but had three beds, perfect for the three of us.

"Let Victoria and I have the beds that are next to each other. You can have the one on the other side of the wall," Laura told her brother.

We all unpacked our things and were laying in our beds on our phones. "Shit, there's no cell service in this place. We're so isolated," Derek complains.

I shrugged. "We will just have to find other fun things to do."

"Yeah, Derek. Don't be such a grouch. I'm going to go take a shower." Laura grabs some clothes and a towel and heads to the bathroom next to our bedroom.

Since Laura is so private about her sex life, I've always wondered how sexual she actually is. Maybe she wants to have sex but thinks it's wrong, or maybe she just hasn't found the perfect guy. I'm much less of a prude than she is, and I've had a few boyfriends before, but Laura has always piqued my interest, ever since her dad and my mom started dating. We've gone on many vacations before as the five of us, and I've seen quick glances of her changing or taking off her towel after a shower. She was very tall, and her long legs looked like they went for days. Her crotch had a small fluff of light blonde hair and her breasts were small but perky. Sometimes I'd find myself wondering if I could get her out of her shell.

I wandered into the bathroom after I heard the shower turn on. Derek was busy reading a comic book so I don't think he noticed. I peeked my head through the door and saw a blurry frame of her body through the blurred shower door. She leaned down to put soap on her legs and feet. I went out of the bathroom door again and knocked loudly so she'd hear me come in.

"Hey, Laura, do you need shampoo? I forgot to put any in there."

"Oh yeah that'd be great, thanks Tori."

Laura opened the shower door for a moment to grab it from me and I subtly observed her body as I handed the shampoo to her. Her whole body had soap bubbles on it, and her short, wet hair clung to her face. Her pink nipples were larger than I expected and looked soft and puffy. My face turned bright red as I was thinking of what I wanted to do to her. Thankfully she didn't notice, took the shampoo, and closed the door again.

I left the bathroom before I could daydream any longer as I noticed the heat between my legs. When I came back to the bedroom, Derek was gone, and I heard him downstairs talking with his dad. I didn't think twice before getting in my bed, under my covers, and quickly taking off my shorts and underwear, leaving them at my ankles in case I needed to pull them up quickly.

I was soaking wet between my legs as my fingers easily slid inside of me. I shoved my hand under my shirt and bra and pinched at my nipples, feeling them get hard at my touch. My clit twitched at the feeling, since my breasts are so sensitive.

I almost came instantly with the image of Laura rubbing soap on her little boobs, and the thought of her maybe masturbating in the shower at the same time as me. I slowly stroked circles around my clit, making myself even wetter, and getting me closer to climax. I continued to imagine her sitting on the floor of the shower with her knees spread apart, letting the water hit her clit as she rubbed it and cupped her breast with her other hand. I wished I could be in there with her. Suddenly, everything tensed up and I came hard. I could still feel a redness to my face and my breaths were heavy. I quickly put back on my clothes, and just in time, as Laura came back in the room.