secret with my sister in law

My wife and her sister have never been really close but over the last few years, her sister has been really trying to get close to the family. She ran away from home at a young age , had kids and is now in her mid 40s and has recently moved back close to us. I've really never said much to her other than be cordial but recently noticed she was starting to wear more revealing outfits. Before it was oversized sweaters and sweats but now its skin tight pants and low cut tops. My sister in law is about 5 ft 100 lbs and b cups but noticed her cups were a little bigger now in her tighter clothes. Lately we've visted her parents for weekend bbqs and dinners and her sister has been attending them more. She recently added me on social media and started posting a lot.

They have plans for a girls weekend and my sister in law was posting about events and matching outfits and one outfit caught my eye. It was a one piece lace lingerie set that first was just the outfit and then her trying it out, I couldn't help but screen shot it to look at it later. I thought to myself, is this how open she is with her sexuality or she post to only a small group and accidentally added me. The next dinner we had at their parents house I got to late and my wife had to leave early to a friends birthday. I stayed and got drunk with their brother and kept running inside to grab more beers and noticed my sister in law in the kitchen cooking. When I went in the last time, she was on all fours reaching into the lower cabinet looking for mixing bowls and I noticed her black g string riding up her jeans. I stood there for a minute just watching until she noticed me. When she saw me, she said oh, hey can you help me reach the plates at the top cabinet. I reached up and looked down at her and saw she either wasn't wearing a bra or just had one on that let her nipple free. As I was bringing the plates down, she lost her balance and grabbed me by my leg but wasn't my leg, it was my hard cock to the the side and she said excuse me and was a little embarrassed. I quickly grabbed my beers and went back to drinking outside.

It wasn't long before I needed to use the bathroom and ran back inside. I went into the bathroom all drunk and thought it was unoccupied but it was my sister in law bent over the sink with her hand in her pants pleasuring herself. I was a little slow to notice that I was just watching until she made eye contact and was like quickly, close the door and lock it. I was so drunk I thought this was one of my dreams, she jumped on the sink with her pants off and said help me. I got down on my knees and looked up at her, spread her legs and just started eating. She had me by the head and was controlling my mouth and pulled out one of her tits and started rubbing. It was intense, I finished eating her out and she came shaking and jumped off the sink and pulled me by the shirt and started kissing me. She said she just needs dick and wanted to see if all the things her sister were true. That's when she got down on her knees and pulled my pants down and started stroking my cock and deep throating. I could tell she was really experienced and she did this thing where she spit on one hand and started rubbing my balls before sucking on them. She then had her hand on my shaft, deep throating and the other on my ass pulling it deeper until she gagged. She quickly turned around bent over the sink again and grabbed my hands and pulled me closer into her. I looked back at her ass and spread it as she reached under to grab my head to rub against her pussy. She looked back at me in the eye and said be gentle, I'm really tight and haven't had dick in 6 months. I thought to myself, is this going to be a one time thing? she isn't fucking her husband? he's outside passed out drunk and I'm in here about to rail her until her back is blown out.

I slowly got my dick inside of he from behind and started thrusting deep into as I grabbed both of her waist. She tried to stay quiet but her moaning got louder and louder. I pulled out real quick to turn on the water to try to cover up the sound of the skin slapping. I kept pounding her from behind and could tell she kept cumming as her pussy squeezed my dick and she kept shaking and almost losing her footing. I picked her up and put her on the sink counter facing me as I slid my dick into her and she looked down watching it go in and out. Her pussy was so creammy and my dick was covered in all of it. She kept kissing me and taking my hand to her throat and I choked her a little and could see it drove her crazy. I was fucking her deeper and deeper and she wispered into my ear, do you want to fuck me in the ass? Its going to the be only time so you might as well stretch me out in all holes. I got so excited i accidentally filled her up with a little bit of cum and pulled her back off and got behind her. I didn't know it but my sister in law really liked anal. My cock was still lubed up from the cum and pussy cream that it slid easy deep into her ass. It was like nothing I have felt before. It was tight on my dick alll the way deep inside and could feel her ass pulsing on my dick. I kept fucking her for another 15 mins in the ass and accidently pulled out to far and she slid it back into her pussy and we went back in forth until I had to cum. I didn't know what to do with my load so I asked and she said fill up any hole so I pushed deep into her pussy and exploded and she came at the same time and we shook together as i held her from behind. She then reached down to her pants and slid them back on , I put mine on and she jumped back on the counter and we kissed. She said this never happened and will be the only time I get to use her. Since that moment, we walked away from it like nothing ever happened and its our secret.

Later that night I got home and was changing into other clothes and realized my sister in law had slipped her g string into my pocket. It was covered in cum and I wasn't sure what to do with it, keep it as a trophy and hide it? return it? I'll see, maybe ill try returning it and seeing if she wants to go another round.