Todd, Jenny and me I'd returned back home early from the confrence I'd attended and heard upon entering our home, three sentences which have changed everything. Firstly I heard the distinct voice of my second wife Jenny say "Fuck me with big cock of yours" Then I heard another voice I knew all too well saying "Which fucking hole do you want it in, you fucking slut" . My wife replied "You've already fucked my pussy boy, I want that huge fucking thing up my asshole". In those three sentences I suddenly knew why my wife was always trying to get time alone with my son and her 19 year old step son, of late. Jenny's my second wife. I left my first wife, the mother of Todd, to begin a new relationship with Jenny, who was twelve years younger than my wife and so much more sexy and sexual. Todd moved away with is mom, but nearly a year ago his mom was killed in a car accident and Todd reluctantly at first, moved in with us. I can clearly remember now the first time Jenny asked me if I was away working and then what time I would be home again, when I told her I would be away for three days. I also remember her pussy and asshole feeling a little looser when I fucked her after getting back home (We still even now, fuck alot). I didn't think anything of it at the time as I knew Jenny liked to fuck herself with her array of dildo's when I was gone. Looking back now it's obvious she was asking so she and Todd could fuck one another and know when I would return. Creeping up the stairs and looking through the bannister into our bedroom, I got a clear view of my sons ass bucking to and thro as he slammed his cock into my wife from behind. I'm a reasonably well endowed guy at eight inches, but seeing my sons cock when he pulled out so Jenny could mount him, I soon realised he was at least a couple of inches, if not more longer than me and his cock was alot thicker too. Watching them fuck was surreal in many ways, not least because different emotions were going through me. At one point I was going to burst in and get all macho, but seeing my beautiful wife's asshole taking my sons massive cock made me become unbelievably horny and bizzarely proud. I sat on the stairs for about ten minutes as they fucked one another. And I listened to their sex talk as each of them spoke about how they wanted their sex to go. I finally moved away, only because my wife spun around onto her back and was facing the doorway with her head over the end of the bed. Todd was lying on top of her sucking her breasts and about to thrust into her, and these were her words "Fuck my slippery wet cunt". All kinds of emotions and thoughts entered my head as I went outside and sat in my car. Eventually I phoned the house phone and waited. Entering the house there was no getting away from the smell of sex, but when I walked in both my son and his step mom were busy watching some brain dead tv show. It's been ten days since I discovered them fucking, ten days in which I've gone over and over what I saw and also over and over what I should do. I know for instance they've fucked again when I've been out at work and I know for sure Todds fucked my wifes pussy. That's because I went down on her one evening and I could taste what I presumed was my own sons essence. It isn't easy making a decision, that's beacuse I know how badly I treated Todd and his mother when he was younger and I also know, well I'm guessing, he's fucking Jenny to get some sort of redress. I'll have to make my mind up soon. If I'm going to let them know I know, or let them carry on fucking one another. After all I'm still getting all the sex I can handle from Jenny when I'm feeling horny.