Riding my Aunt

Uncle Frank my father younger brother is married to Megan both in their forties, one son who is at university. I'm David 22 carpenter youngest of 3 (only boy) to Graham and Heather, I live at home in the room over the garage. I don't pay rent and can come and go without question and washing done and meals provided. I have repaired some parts of the house and always assist my mother with any heavy gardening work that she is doing. Frank and Megan live next door and always have as far back as I can remember. I'm the only child not to go to university as I like working with my hands. Frank travels every second week of each month to different places for his work. Leaving Megan home alone, last June both of my parents went to see their first grandchild and visit my sister Grace and Mike her husband. Frank also went away and thus Megan was home alone and without Heather to talk too. The first night I was alone at home there was a knock on my door, it was Megan. She had been drinking and felt lonely and came over to talk, she quickly felt asleep and so I put her on my bed and covered her with blanket. I laid down the old padded bench I had and went to sleep there. It was a Friday night and I didn't have any work next day and was planning to work on my pickup. I was awoken in the early hours by furniture being knocked over. It was Megan she wanted to go the toilet and couldn't find a light switch or the toilet door. I had turned on a light and showed her the toilet, after she got back on my bed and just sat looking at me. I thought she was confused by being at my place, but she wasn't. She was horny and was thinking about asking me to fuck her and tossing up in her mind her chances of getting fucked by me. Finally she asked me would I do her a great favor and fuck her, I was shocked a little at first. But decided why not she passed getting pregnant and I've always liked her and used imagines of her in her bathing suit to help get me off while masturbating. I've had some success, but was between girlfriends at the time. So I joined her in my bed and fucked and fucked again in the morning. Later on in the day I was working on my pickup and Megan came over with lunch for me and we fucked again on my pickup's seat in the garage. I never knew how horny a woman Megan was, during the whole time my parents were away she was visiting me for sex. I wasn't visited by her when Frank was home, but as soon as he was away. She came over for sex from me, even with my parent in their house. I loved our sex sessions. In September I met Wendy and we started dating and getting very serious. But Megan didn't care that I now had girlfriend, she just wanted fucking when Frank was away. Even with Wendy living with me now, she always finds a time to fuck me went Wendy is either at work or shopping. Wendy and I are marrying shortly and I've bought the house behind my parents home with their help. Megan is still wanting sex and last week I came home and caught Megan in bed with Wendy and shocked at first, but not enough to stop me joining them in a threesome. Megan smiled at me as she was leaving and said now we don't need to hide from Wendy. Frank went away last week and Megan was over sharing our bed having threesomes. Wendy has just been confirmed as pregnant and Megan and her are as thick as thieves.