My pregnant sister

I'm Karl 36 single and lived by myself till last November, I've never been a ladies man. But have had some success, but nothing that led to a relationship. In November my sister Joyce 29 youngest of my siblings came to live with me. She was pregnant and had lost her job and the father of her baby had left her and she didn't know where he went and nobody that knew him or his family knew or would say where he was. Joyce came to me as she didn't want to face our parents over her pregnancy. It was strange having a woman around my home and I couldn't lounge around naked as I used to do before her arrival. Being almost 5 months pregnant at the time of her arrival, Joyce was depressed by the desertion of her boyfriend and being pregnant as well. About 2 weeks after she moved in with me, she had gone to the mall for some things as she wanted to get out of the house for a time. I had given her my card to buy what she needed and get something for lunch as well. Shortly after she left to walk the block to the mall, I got on my computer to watch some porn and masturbate myself. I didn't hear her return shortly after and when she came into my room and caught me dick in hand I was shocked. She just smiled and said she had needed to pee and returned home and while peeing decided to ask me to join her on her trip to the mall. Thus catching me cock in hand, she was the first to say someting and asked did I want a hand, I looked her and she then just came over to me and took hold of my cock and started to stroke it. I just let her do it, then she stood up and undressed completely and said I could play with her tits. Putting my hands on her tits, I started to relax and enjoy her playing with my cock, then she went down on me and that caused me to blow my load and she took in all in her mouth and swallowed it. She got up and led me to my bathroom and we showered together. I got another hard-on and she told I could insert it into her and so I did and I blew my second inside her. After as we dressed she told I didn't have to masturbate while was living with, as she would take care of my needs as a thankyou for helping her out. We went to mall together and had lunch there and on returning home I thanked her for the fuck and she replied anytime. This caused my cock to harden again and we spent the rest of the afternoon in bed together. That night she slept with me and everynight since. The baby is due in several weeks time and she still has sex with me. My mother is coming soon to be here for the birth and we will have to sleep apart while she is here.