Okay, not going in to too much detail, my parents divorced when I was 16 and my dad remarrie when I was 18. The woman he married has a daughter who is only a year younger then me and is incredibly good looking (looks a hell of a lot like the pornstar Tori Black).

We'd been quite close for a while and had a good laugh with eachother but then I joined the gym and put on just over a stone in muscle in just over a month thanks to a strict diet and gym routine.

One time I was getting out the shower but forgot to bring a fresh towel in with me from the airing cupboard and seeing as my bedroom is right next to the bathroom I thought I could make a quick dash without anyone seeing me. Needless to say I was wrong lol. She ended catching me stark naked and seemed shocked in a good way.

Soon after that she started flirting with me quite a lot when nobody else was around and loved touching me. I didn't think anything of it really as I just thought it was a bit of playfulness....but things changed in September.

I'm in my second year at uni and she just started her first year at the same uni. I looked after her during freshers week but she ended up getting drunk one night (even more then me). We went back to my uni student house and I put her to bed on the sofa and thought that was that. I ended up waking halfway through the night with her somehow of having stripped most of her clothes off (leaving just her french knickers on) and she'd made her way in to my bed.

I'm pretty sure she was asleep at this point but her hand had strayed a little south for my liking and was half way in to my boxers so I tried to pull it out without waking her up. I failed miserably, she woke up and accused me of trying to make her give me a handjob in her sleep. I thought she was deadly serious but then she chuckled, ended up kissing me without warning. One thing led to another and we ended up having sex for almost 3 hours.

That was almost 3 months ago now and we've had sex so many more times since then in all the craziest places you can imagine....we even had sex in the car on the way back to my dad and her mums house for xmas when we got stuck in the snow and ended up spending the night in the car. Don't get me wrong, I think she looks incredible and she gives the best sex Ive ever had and I know it's not illegal in the uk but there's a slight problem...

...a couple nights ago we went to a house party of a mate of mine and me and my step sister ended up having sex in the parents bedroom. Someone walked in and saw my face but my step sister managed to hide hers quickly. I've talked to the person who walked in and I'm pretty sure they think it was my sister.

Should deny everything and say it was just some random girl, say I don't remember cos I was so drunk or admit everything and tell everyone that me and my step sister are seeing eachother?

I don't really know what peoples social views are on relationships with step-siblings. Any views/opinions are greatly appriciated. Thanks..

@Esmo - no. i haven't brought it up with her. we do everything a bf and gf do apart from actually discuss the subject of what others would think. i dont know whether shes just nervous about telling people in case they think we're strange or whether shes just interested in being with me for the sex. by her own words im the only guy who's ever made her orgasm on a regular basis (i even made her squirt one time).
tbh i dont think my dad and her mum would deal with it too well either. im a bit concerned all my mates and all of her mates would take it....