Staying with my future sister.in-law [MF] [Cheating]

Names are altered for obvious reasons. Mistakes and bad wording probably are because English isn’t my first language.

I am an archaeologist and was on a longer job ways away from where I normally live and work. And stayed at Mary’s, my fiance’s sister, place, because she had a spare room at the time, after her roommate had moved out.

Mary is in her mid-twenties, athletic and redheaded. Aside from minor differences and her hair color she looks a lot like her sister. So it is safe to say I find her very attractive as well,

On the few occasions I have met Mary we actually got along quite well. We were never really alone with each other before.

After a long work day, I went out with some colleagues from the excavation I was working at. After drinking my fill I took a taxi to Mary’s appartement.

She was sitting in her living room on the couch, watching TV. In my drunk state I joined her on the couch after a short while we were joking around. We talked about my fiance’s joke, when she arranged for me to stay at Mary’s, that I shouldn’t try to seduce her sister. Mary joked maybe she should try to seduce me then, as that had not been forbidden.

She kissed me as a continuation of the joke at first. But me still being under the influence and Mary not being sober either escalated pretty fast after that.

We were still clothed but pawing and groping each other heavily. When Mary felt my semi hard-on through my pants, she yanked it out and started jerking me off with slow massaging motions increasing in speed. I couldn’t help but sit back and moan under heavy breaths. I stopped her hover before she could finish me off.

I stood up, took off her hot pants and underwear and started going down on her. I licked her shaved pussy and used one hand to massage her breasts above my head through her shirt and bra, while I used the other hand to supplement my oral ministrations, and stimulated her clit and pussy.

Her breaths grew shorter and shorter until she started squirming in her seat and moaning. I could tell she was nearing her climax. My mouth worked my´´its way up kissing her from her lower to her other lips.

That was when I completely got rid of my pants and positioned myself at her entrance. I was at full attention and entered her slowly. She was tighter than my fiance, But just as wet and warm.

I kept rubbing her clit with one hand, while I used the other to steady myself against the couch and hammering away at her. Both of us were breathing heavy and moaning at this point.

Thanks to the cool off period I had had and the work I did on Mary before, she climaxed under me. Squirming and shaking lightly. I stopped moving, giving Mary a few moments to get herself together.

We took the rest of our clothes of and continued for a few moments in missionary on the couch, before Mary wanted to switch and so she rode me cowgirl style, while massaging herself. In this position Mary had another orgasm, shuddering and moaning on top of me.

I removed myself from under her and she landed on the couch on all fours. I took the cue and took her doggystyle. Sadly enough my stamina was spent and I could feel my limit approaching.

Mary was still moaning from pleasure, but nothing in the world could have kept me going at that point. I told her I was at my limit and climaxed hard inside her.

We both collapsed on the couch in a stupor of orgasm and alcohol and fell asleep.

Source: reddit.com/r/gonewildstories/comments/9aqt3v/staying_with_my_future_sisterinlaw_mf_cheating