I was at school talking with my girlfriend, Ashley in AP anatomy class. We were talking of how far we've made it together and when we first started going out. We were both in 11th grade and have been dating since 8th grade and we were both faithful.. Well until the summer started. I always dreamt that I would lose my virginity to Ashley. We made a promise in ninth grade that we were going to wait until graduation night before we had sex for the first time. 

Ashley was middle height, about 5'5 and small perky breast of 32B. She had long gorgeous blonde hair and eyes so blue that you could melt into them. 

The most we've ever done was I touched her breasts and she played with my cock from the outside of my pants. We've been more than tempted to try more though but never did. 

The summer after eleventh grade ended, I planned to go on a camping trip with Ashley, her twin brother Matt, and her sister Mia. Ashley and Matt were 16 like me and Mia was 17. The trip was going to be for three weeks and I was going to attempt to have my first with Ashley even though we made the promise. 

I was getting ready for the trip when Ashley called me. 

"Hey, Luke, you ready for the trip? Were going to be at your house in an hour!" Ashley said all excitedly. 

"I definitely can't wait!" I said with the thought of having sex with her. 

"I can't wait to spend the while trip with you! We can probably sneak off while were on a hike, maybe gave a little fun, if you know what I mean."

I knew exactly what she meant; she meant a makeout session, but I had other things in mind and so did my cock. 

"Oh I do know what you mean," I said in the same type of voice she did. With my cock bulging in my pants, I decided to make an attempt at not relieving it so when I'm alone with Ashley, I'll be extra horny. "I can't wait to see you, but I gotta finish packing my clothes. I love you so so much and can't wait!"

"I love you too! Bye!"

After a couple minutes of laying on my bed listening to music, my hard-on went away. I hopped in the shower and finished the last of my packing just in time. 

I ran downstairs when the bell rang and saw my girlfriend standing there. Before I knew it, we were tongue wrestling for a couple minutes before her dad honked the van horn. 

Me and Ashley sat in the way back with Mia and Matt sitting in the middle. On the way to the camping site (an hour and a half away) we talked about things we were going to do there. They brought along two jet skis because there was a lake right at the camping site, so I knew we would be busy on those a lot. We talked about a lot of other things but I still had my plans in the back of my mind. 

We finally got to the campsite and we each set up our own tent. Everyone had their own except their parents which were sharing one. Ashley put her tent right next to mine and Mia was on my other side. Matt was at the other end next to Mia It was almost dark when we got there so we ate some dinner, made s'mores and went to bed. I went into Ashley's tent to kiss her goodnight. She didn't know about my plan to sneak in there later tonight. I went to my tent and tried to stay awake. 

I fell asleep and woke up about two hours later. Perfect timing for my plan! I poked my head out my tent and when I saw that no one was awake I headed to the tent to my right: Ashley's tent! Even though it was dark in there, I still had enough light to see her peacefully resting there in her sleeping bag. 

"Hey, wake up. I have a surprise for you." I whispered while nudging her a little. I hear her wake up and right as she faced me, I went straight in and kissed her. 

She was confused at first, I could tell because she didn't kiss back at first but when she woke up a little more, she kissed me with an intense fury I've never felt from her before! 

I took my chances and talked to her.

I said, "do you know to know my surprise?"

I went back to kiss her and he faintly mumbled yes.

"Well I'm here to take something that will never be returned." I kissed her again and she moaned by the intensity signalling that she knew what I meant. 

I care fully took of my shirt, breaking the kiss for no more than a second. I noticed she was doing the same, and she took her bra off too. I decided to take her pants off and she did the same to me. Through her panties, I could feel she was already wet. I starting massaging her lips and then took her panties off. She stuck her hand down my pants and started stroking my cock.

I removed my boxers and so badly wanted to put my cock 6 and a half inch in her virgin pussy but I decided to start by fingering her.

I started by sticking one finger in there and when I saw that it didn't hurt, I put my middle finger in there too. I moved them slowly at first and then I got faster and faster until you could her a squishing sound from her pussy being that wet. My other hand fondled a breast. I started playing with her tit, which felt bigger than I thought. I squeezed and twisted her nipple. 

"I knew you would like this! Ive been waiting so long to do this to you! You like me fucking you with my fingers don't you?"

Her moans grew louder, but with all the crickets and other animals making noises, it didn't seem as loud. I felt her about to cum but before she did, I stopped finger fucking her and though I felt her disappointment, she started taking over and starting stroking my cock faster and faster. 

I was moaning louder than she was. She felt like a pro! She said something but I couldn't here her over my moans. She caressed and played with my balls with her other hand. I was about to cum and she dud the same thing I did to her; she quit giving me a hand job. 

"Put that cock in my hungry pussy," I heard her whisper faintly. 

I started rubbing my cock against her lips to get it wet with her juices. I led my cock to het pussy and inserted the head. She moaned loud and knew it must have hurt. 

I inserted it slowly until my whole cock disappeared. I pulled it out slowly and then in again. I picked up the pace every time and before I knew it, we were going really fast. 

I felt her about to cum when she practically yelled. 

"Oh god! I'm cumming! I'm fuuuuucccckkkkkiiiinnnnn coooooooommmmmmmiiinnnnnggggg! Fuck, Lukkkkkeeeee!" she said right before she came.

I pulled out of her and held my fingers near her opening where she was gushing like crazy. I brought my drenched fingers to my lips and tasted the most sweet taste ever. 

She helped me cum by stroking me while we kissed and she got a taste of her own cum. 

After we were done, we cuddled inside her sleeping bag naked. I held her in my arms and decided to play with her tits one last time before I left. As I started running my hand over them, I realised that they felt bigger than before. 

"When did your tits get bigger? They have to be at least a C!" I said while still playing with them. 

"They've been a C since 7th grade, Luke," a voice said that was not my Ashley!

I stopped playing with her breasts and kind of sat up to take a look at her. C breasts, wavy dark brown hair, maybe as tall as me! Who was this chick that I just fucked!? I looked at her one more time. 

"Oh god. Oh god! Mia!!?? What are you doing here? This is Ashley's tent!"

"Ooh my god. I thought you knew it was me. Oh my fucking god!!" Mia said freaking out. 

"Why are you in here!" I said putting emphasis on the word you. 

"Me and Ashley switches tents because she was scared to be on the very outside!"

I didn't know what to say. I just fucked my girlfriend's older sister! And most importantly, even though I knew I wanted to do it again! I LIKED fucking her! I was getting another erection just thinking about our fuck session. 

"I-I think I should go b-back to my tent n-now." I stuttered the sentence. I wanted to get out of there before she saw my newest erection. 

"Wait!" was all she said and I didn't move. "you liked it, didn't you? I know I did. Probably the best fuck I've ever received. And something tells me you loved what just happened." she said looking down at my erection. 

"Ok. I admit it. I didn't like it.. I loved it! And now I'm a cheater!" I said feeling like I was about to cry. 

"It's ok. It was a mistake. Things like this happen." Mia said while stroking my cock. 

Before I realised it, we were back to making out. She stopped kissing me. 

"You know, I know about the promise you and Ashley made. It's going to be hard for you too keep after this." I nodded in agreement. "Everything changes after your first time. If you wanted, maybe we could do this again. For your sake!" I was about to say no when she cut me off. "We could have sex when you need the release. We could be friends. Friends with benefits."

I gave it thought. Could that really work? I know that masturbating after that would be nothing in comparison. 

"Nothing more than just sex?" I asked. 

"Nothing more. I promise."

Mia got close to me and I met her halfway and made out with her. She gave me one more handjob before sending me back to my tent. I could hardly sleep at all. I wad cheating on my girlfriend with her sister! I was becoming sexually active. I didn't know how I was going to do it but I was going to.