My girlfriend's sister likes me more than I thought...

I am 19M and my girlfriend 18F. Her sister is 14F and her body is going through changes, including sex drive.

My girlfriend always had a good relationship with her sister. They did everything together. My girlfriend is 18, about 5 ft, dark hair, chubby at 65kg, and her sister is 14, about 5'1, blonde hair, and skinny at 40kg. Usually, when I'm not there, they'll just sit together and talk, play games, watch TV, either way whatever they were doing they did it together.

I never really mind what we do, and so I just do whatever they're doing with them. I am 19, 6'3, long dark hair and about 95kg. This one particular evening, I was sat with my girlfriend at her parents house, her head resting on my lap as we watched TV with her sister, who was on the other couch. She was cuddled in a blanket, and complained that she is warm. I recommended that she take the blanket off, and she said she couldn't, as the clothes that she was wearing were quite revealing. I reassured her, saying that I'm not one to judge, and considering its her house, she can wear what she wants. My girlfriend said that she was tired, and wanted all of us to go upstairs. Me and her sister agreed, and we all went upstairs. For the sake of mine and your sanity and their privacy, we'll call my girlfriend Hanna and her sister Faith. Initially, Hanna went into the bathroom, so me and Faith went into their shared bedroom.

Faith again complained that she was too warm, so I told her to take the blanket off. She said okay, and dropped the blanket. Immediately, I saw more on her than I ever have before. A thin tank top showed me enough to say that she had B-cup perky tits, and I could see her nipples as they poked through. She had a camel toe and a small thigh gap. She looked perfect. In the mirror behind her, I could see the bottom of her ass cheeks under her tight shorts. I didn't make any comments, keeping in mind what she had said before, and I didn't want to freak her out, so I silently appreciated the view.

Hanna came back in and pulled out a small bottle of vodka.

"Faith, wanna try your first drink? You can mix it with some coke" my girlfriend asked with a slight grin.

"Are you sure? She's 14, your parents will be so mad if they find out" I said. Personally, I believe the concern was reasonable, as her parents werent the greatest. Although they were never physical, theyre very manipulative and emotionally abusive.

"It'll be fine, they won't find out. They'll need to actually check on us for that" she replied. This was also very reasonable, their parents were neglectful and if Hanna and Faith stayed in their room all day, they simply wouldnt see their parents.

Faith really wanted to try it, so she went and got some Coca-Cola out of the fridge and a cup, and we mixed a shot into some coke. After a little while and 2-3 shots, she was starting to get tipsy.

Hanna and I had laid some blankets on the floor, and we were cuddling together. She liked the extra space the floor gave. Faith got out of her bed and came to join us. My legs were slightly open, and she just placed herself between them. There was nothing too awkward about it though, we were both fully clothed. Until about 5 minutes later.

"I've never seen a mans cock before. Can you show me?" Faith asked, with such innocence in her voice. I was confused beyond belief, and wasnt sure if my hearing was deceiving me. Then when Hanna asked "what??" I knew it wasn't.

"Faith, youre just a kid. I can't show you that." I was concerned, and couldn't believe we were even having this conversation.

"I really want to see it though, I've seen pictures but I wanna see it for real." She was pretty much begging at this point, and I was considering giving in. One thing I forgot to take into consideration is that Hanna is a very horny drunk. She doesn't care about sex when we're sober, but once shes had a couple drinks, she becomes a sex addict. Before I could even react, she had her thumb wrapped around my waistband, teasing faith with the sight of the base of my cock.

"Babe what are you doing?" I started to panic internally,  but a part of me couldnt deny I was loving it.

"Faith, watch how I do it and then you can try it yourself" She said. And with that, my full 8 inch cock was exposed to Faith. Her eyes lit up, she was so excited to see it. It was a short lived sight however, because a few seconds later, Hanna was bobbing her head up and down with my cock in her mouth. She pushed herself as far down as she could and got a little over halfway, then pulled away, a string of saliva being the only thing left connecting my cock to her mouth.

"Your turn" she told Faith. Faith looked a bit scared, which I could understand, it was her first time even seeing a cock and now shes about to suck it. She took the base of my cock in her hand and kissed the tip, licked it gently and then managed to push the head into her mouth. She moved up and down, just as she was shown, but her teeth were scraping against the top. I let her know to try to avoid allowing her teeth to make any contact, and then suddenly it felt so much better. For her first time, her mouth felt amazing. Again, just as she was told, she pushed her head as far down as she could, and could barely make it halfway before gagging and pulling away.

Hanna tried to take over, she grabbed the base of my cock and tried to pull it away, then Faith quickly took it back into her mouth. Hanna realised what was happening, and took one of my balls into her mouth. I was in heaven. I felt my orgasm approaching, and so I told them "I'm gonna cum soon".

Hanna smiled and pulled Faith back.

She told Faith to sit on her knees, and lifted both of their shirts up, and I could see both of their tits. Hanna had huge ones, at 32FF, and she loved to tease me by playing with them.

"Open your mouth and wait. Do it on her face, honey" Hanna said. Faith listened really well, and she opened her mouth and looked at me in the eyes as I jerked off, looking at both of their chests and faces.

I let them know that it was about to come out, then I shot my warm load all over Faith's face, hair, and chest, some getting onto Hanna's face and chest too.

I was spent, having just received the best blowjob of my life and cumming all over my girlfriends little sisters face. We are definitely going to be having more fun in the future. I hope you liked this story, and keep an eye out for any others!