First let me get some background information out of the way. My name is Jake and I was sixteen when this story took happened. I didn't have many friends back then as I attended a boarding school with my sister, Sofia, after our parents won the lottery.

Our parents won a lot of money in the lottery, and they bought some businesses around the world which meant they had to travel a lot. They decided our education was very important so they sent us to a boarding school, as they didn't want to leave us at home alone as they travelled. Due to the fact I came from a now wealthy family, guys would start to be nice to me, trying to become good friends with me in hope I would spend money on them. For that reason, I only had two true friends in the whole school, my sister Sofia and a guy called Alex.

When I first arrived at the school, I needed to take up an activity to stay busy so I decided to start working out in the school gym. The school gym wasn't overly fantastic, but it had everything you could need in it.

I started to work out a lot, spending most of my free time in the gym alone working out. There was one guy that was always in the gym at the same time as me, and he also happened to be one of my roommates. His name was Alex. He kept to himself, and didn't try becoming friends with me to avail of the benefits of being rich. We started working out together, as it's better to work out with a partner.

Soon we became good friends so I introduced him to my sister at dinner one day, and they started talking. My sister's friend Sarah and Alex really hit it off fast, and were soon boyfriend and girlfriend and spending a lot of time together. It wasn't long before I wasn't hanging out with Alex anymore except in the gym and sometimes in the dorm room when we had to stay in our rooms. It was the same for my sister, which drew us together even closer than ever.

I am quite muscly, due to spending a lot of time at the gym out of boredom. I have black hair, which I try to keep short. My sister is sixteen and they're ten months between our birthdays. She looks younger in than me in facial appearance, but her body is like a full grown women’s.

She started working out at the gym with me out of boredom, and she managed to get herself an amazing ass and body. She would wear yoga shorts in the gym with a tight belly top and the clothes really showed off her assets.

The story begins one day in the gym. Alex had just left as it was a Saturday morning and we were allowed into the town on the weekends. Sofia and I had decided not to go today, as there wasn't much to do there besides sit around on the grass in the sun. We decided we could do that at the school rather than having to take a twenty minute bus ride to do it. We decided it was time to finish up so we went into the changing rooms of the gym.

The changing room is just a big room with lockers along the wall and benches in the middle, and it is unisex. There are two different shower rooms in the changing area. Normally when we go into the changing room, my sister would take off her clothes in the shower room and then bring them back out with a towel wrapped around her and put her clothes in her locker. I always stripped where I was and I was normally in the shower by the time she came out with her clothes. We both have lockers beside each other, as it goes alphabetically by surname.

Today, she went into the changing room and stripped bare in front of me, not caring that I could see her. We both stood naked looking at each other’s bodies, and I lusted for her so bad. My cock became rock hard, and I made no move to hide it. She smiled at me, grabbed her bag of shower stuff, and disappeared into the shower without another word.

I went into the guys showers, and started to stroke my cock hard, fantasizing about fucking my sister hard in her pussy which had a small bit of hair around it in a cute little triangle. I thought about her breasts, and how amazing they looked. I guessed they were a C cup.

Soon cum started to shoot out of my seven inch cock and I finished washing in the shower, before I stepped out into the changing room, not bothering to wrap a towel around me. My sister was still in the shower, as I could hear it running. I longed to see her naked body again. I dressed slowly, hoping she would emerge soon.

Finally I was dressed, and I sat on the bench waiting on her, as we had plans to hang out after the gym. Soon she came out, naked and without a towel. She had shaved her pussy clean, and she was still soaking wet from the shower. She didn't speak or look at me, she just proceeded to dress. She put on her dress, completely forgetting her bra and panties, and we left the room.

We went outside to the grass area in the sun at the back of the school near the dorms and sat down under the big oak tree.

We started talking like we normally do, discussing what’s happening in our classes and with the guys and girls who kept being nice to us to try and avail of our money. She sat in front of me, Indian style and I could see her pussy. I tried to stop looking at it as we talked, but I couldn't.

"Why do you keep staring at me?" she asked suddenly.

"It's nice to look at the person talking to you," I stuttered.

"Yeah, it's nice to look them in the eye not between their legs," she laughed.

"Sorry I can't help it," I stammered.

"I know that's why I'm not wearing any panties," she said seductively.

"You like showing your brother your pussy?" I asked.

"I love being a tease Jake, and you’re the only person I can be a tease to," she said.

"You could tease other people too."

"Yeah but then one of them might tell a teacher. I was walking around without a bra on in my white school shirt on Tuesday and you could see my nipples. One of the guys in my class was going to tattle on me so I had to let him have a feel of them," she said.

"Who was it?" I said angrily.

"It doesn't matter," she laughed. "He wanted me to suck him off but his dick was really small so I didn't. If he try’s anything again I'll just tell everyone."

"Smart girl," I laughed.

We sat in silence for a while, wondering what to say next. A few teachers walked by and we greeted them. The teachers in the school were always very nice, except for one. The one teacher that is horrible to everyone walked by, and snapped at us saying boys and girls shouldn't be sitting that close to each other. Sofia shouted at her saying we were brother and sister but the teacher seemed about to hand us detentions before our favorite teacher, Ms. Baxley walked by and saved us.

Ms. Baxley was a young teacher, only in her early twenties. She was the guidance counselor in the school and also though Physical Education, which Sofia and I excelled at, making her like us a lot. She asked us to come up the gym with her, and help sort out equipment for her classes as she had to get it done and it would go faster if she had help. When we got to the gym storage room, Sofia and I got to work sorting out all the equipment while Ms. Baxley disposed of the broken and old stuff.

"I'm going to have to go and get more bags from the maid’s office, we've run out. I'll be back in about twenty minutes. You can take a break if you want. I'll bring back a snack," she called to us before leaving.

"It's really hot in here," Sofia said.

"I know I need a drink," I said. I took off my t-shirt and sat down on the old bench in the room.

"Don't stop stripping now," she laughed.

"I think it's only fair your take something off now that I have," I smiled.

"I'm only wearing one thing Jake!"

"I know that’s the great thing about it," I laughed.

"Fine then," she said. She reached around the back of her dress and pulled the zipper down, letting the dress fall to the floor.

"You have an amazing body sis."

"You too bro," she said.

She walked over to the bench and sat on my lap. We started to kiss each other, letting our tongues dance in each other’s mouths. Her hand was at her pussy, rubbing it slowly which made my shorts get a little wet from her juices.

"Your shorts are getting wet, Ms. Baxley is going to notice the wet patch if we keep this up," she said to me.

"We can fix that," I said as she stood up. I pulled me shorts down to my ankles and kicked them off.

"Much better," Sofia said, climbing back onto my lap. She started to stroke me cock slowly as we kissed, and my hand slowly rubbed her pussy from behind. "This feels so good Jake."

"It does for me too Sofia," I groaned, as she started to wank me faster. She kept wanking me and I knew I was going to cum soon. "Sofia I'm going to cum," I groaned.

"Cum on me Jake, cum on me!" she moaned.

I came hard, shooting strings of cum onto her stomach. She stomach was soon covered in cum.

"Well this is a mess and seeing as there are no towels around you’re going to have to lick me clean," she smiled.

I started to lick my cum off her stomach, making sure I got every bit of it to make her happy. It was the first time I'd ever tasted my sweet cum, and my first time ever doing anything with a girl, let alone my sister. When she was clean, we kissed so that I could let her taste my seed. We got dressed and waited on Ms. Baxley to come back, when we had a snack and continued helping her.