My sister Karen

My sister Karen 23 is a party girl and goes out partying every chance she gets, I find her passed out every now and then. Back in June, I arrived at her apartment get a suitcase she had said I could use for my trip. I had my own key and let myself in and I found her passed out lying on her bed where she crashed on getting home earlier. Her dress was up at the back showing her nice arse and I got excited and just had to touch it. She didn't react and so I went a bit further and pull her panties down a bit. I was soon fingering her and decided to fuck her and she seemed to enjoy the fucking. I got carried away and blew my load inside her. I cleaned her up a bit and left. I didn't see her for a week, as I was away on my trip. When returning the suitcase she was home and happy to see me and asked about my trip and how I was going. Then she asked me had I enjoyed fucking her and I was shocked at her knowing at first. but said I had enjoyed it a lot. That's good she said then adding how about fucking me again now. I was still a bit shocked and just nodded and she led me to her bed and we had sex. She told me that when I had fucked her before, she had woken up from her sleep and seen me fucking her in the mirror on the closet and as she was enjoying the fucking let me finish. Also, she wanted me to fuck her on a regular basis. She enjoyed having sex, so I saw her a couple of times a week before moving in with her. She introduced me to her friend Linda 22 and we have threesomes together. Last week our sister Donna 19 came for a visit and Karen seduced her and Linda joined in as well. I found the 3 of them in bed together when I got home from work and was invited to join them and I did. Donna is going home on Friday so I'm making the most of her while she is here.