I was away on business for 3 days a while back and when this happens, my wife and I will occasionally send each other some naughty pics of each other. On this one night, I was in my hotel room lying naked on my bed, with my hard cock in my hand when I snapped a picture of cock and prepared to send it to my wife. I attached the picture to my email and lazily began to type in her address. The auto-fill function on my email completed her address for me after typing in the first few letters and I clicked send. That’s when my heart sank. I realized I was looking at an email that was just sent to my wife’s sister. Their names are very similar and begin with the same letter and I hadn’t even realized at the time the wrong name was added. Oh no.

My wife and her sister are both in their mid-30’s and my sister in law is also very attractive like my wife. We are very friendly with each other, but not to this extent and never really sexually. I instantly panicked while sitting there, not knowing what to do. I decided the best thing to do was email her again and apologize for sending her the picture that showed me from the waist down holding my hard cock in my hand. I briefly explained to her this was meant for my wife and I had somehow accidentally sent it to her. I’m sure it sounded like a bunch of crap, but I immediately sent the 2nd email to her trying my best to explain.

About 40 minutes later I get a response from my wife’s sister in my inbox. My heart sank again when I saw the email and I was afraid to even open it to read what it might say. I took a deep breath and clicked on it.

My sister in law’s response:
“hahaha… no worries. My sister is a lucky girl if she gets to play with that all the time. Thanks for the free show!”

It was such a relief to read her response and realize that she was very cool about the situation. I emailed her back and thanked her for understanding and made a comment that now she knows how perverted her sister and I are while I’m away on business. I also mentioned that I was glad I didn’t accidentally send her the short video I made on my last business trip. (I realized at this point I was provoking the situation a little bit).

This is where it got interesting.

My sister in law’s response:
“A video?? Wow… I can only imagine. Well, if you ‘accidentally’ send that to me I promise I won’t view it, wink wink!”

Damn. Should I do it? Will she think I’m even more of a perv if I follow up on it? (if that’s possible.) Being that I had a few drinks in me, I thought what the hell. I found the video, attached the short video of me masturbating and clicked send. It was about a 3-minute video of me sitting on a chair and masturbating. At the end, I shot 3 or 4 long ropes of cum all over my chest and stomach. Needless to say it was very graphic.

My sister in law’s response:
“Wow! Is all I can say. I must admit you made me a little wet watching this!”

I couldn’t believe I was having this conversation with my wife’s sister. Unbelievable.

I emailed her back and said I was glad she liked the video and now I have something to think about the next time I played. I told her knowing that she’s seen me cum was a huge turn on.

Over the course of the next few days we emailed each other back and forth about a dozen more times. I won’t bore you with all the details but where we left off was that I told her I would love to secretly masturbate for her in person the next time the situation presented itself. She brought up that in about a month our families would be getting together at their parents large cabin for the holiday. “That might be a fun time” is what she said.

Fast forward a month later and our families were together all staying in the same house, along with my in-laws (it was a huge cabin). We would be there for 5 days.

When we first saw each other we gave a coy smile and a polite hug as we always do. There was so much sexual tension in the air I was afraid everyone else would notice. The long weekend began and my mind constantly raced as to when or if this was going to happen. I didn’t want to be too persistent but I was constantly aware of every situation to see if any time presented itself as the right time. It was tough. There were so many people in the house there was hardly a moment any of us were alone.

On the second night, my wife’s sister and I found ourselves alone in the kitchen making some drinks to take outside to the bonfire. We knew it wouldn’t be long before we were no longer alone so I told her that I was a little embarrassed seeing her in person knowing she’s seen ‘all of me’. To my surprise she said, don’t be embarrassed and that over the past month she’s thought about it a few times while she was alone. Wow, did she really masturbate thinking about me? My mind raced with these thoughts. I told her what I turn on that was and that I thought I was going to need some relief very soon.

“Oh really?” she said. I instantly came up with a plan in my head and told her that in about 30 minutes I was going to excuse myself from the bonfire outside to use the restroom and go to a particular bathroom for some ‘quick relief’. I said, “If you ‘accidentally’ walked in on me you might catch me cumming again”. She looked at me and gave me that coy smile and returned to the group outside.

We joined the rest of the family around the fire and drank and had some laughs for a bit. About thirty minutes later I decided to make the move. I casually got up from my chair and told my wife I needed to use the restroom and I’d be right back. She gave me her empty wine glass and asked for a refill on my way back out. Her sister gave me a quick look but I was unable to tell if she was going to follow through or not.

I went to the bathroom next to our rooms where were sleeping. It was a bit out of the way of the back door and kitchen where the group was. Upon entering the bathroom, I quickly unzipped my jeans and pulled my cock out. I began stroking it and getting it hard, hoping that my sister in law would show up. I was nervous but excited at the same time. I couldn’t waste time if she did show up, so my plan was to fully hard and ready to go.

Then it happened. I heard a faint knock on the door. I opened the door just slightly and saw that it was indeed her standing there. I opened the door and she had the biggest smile on her face. She didn’t want to come in and shut the door because that would just be bad and we needed to be on the ‘lookout’ for family members. She stood in the doorway and simply said, “Do it, I want to see”. And for the first time in person, I slid my boxers down and exposed my hard cock for her to see. I started jacking off hard and fast for her. She just stood their staring my cock as I stroked for her. This went on for about a minute and she said “Hurry, cum for me”. Being extremely turned on by the situation it was easier than I thought considering the pressure of her telling me to hurry. I turned slightly to face the sink and started cumming all over. She stood there and watched me cum and it was such a turn on. This entire episode probably lasted a minute but it was still great. I stood there in front of her, cum dripping down the shaft of my cock and all over my hand and just soaked in the moment. As I began to clean up she surprised me again and reached out and cupped my balls and gave them a little squeeze and said “thank you” and walked away.

She returned to the group and a few minutes later I joined them all with re-fills in hand. Nobody suspected a thing.

Over the next few days we would secretly flirt with each other verbally when we found ourselves alone for a second. It was a fun game of cat and mouse trying to avoid getting caught by our family members. I would tell her that I just jacked off in the shower thinking about her ass and things like that. I kept reminding her how much I enjoyed looking at her ass and how I wanted to feel how wet she gets and we had a great time teasing each other back and forth.

On the second to last day of our vacation we were all getting ready to go out of the day. My wife’s parents were on the complete opposite side of the cabin with their own bathroom, etc… My wife and I were in our own room right next to her sister and her husband’s bedroom. We didn’t have our own bathroom room but we all just ended up using the same one that was near our rooms. This morning was our last but most exciting encounter of the weekend. My sister in law was the first in the shower that morning and when she got out she went to her room to finish getting ready. As soon as the bathroom was empty it was my wife’s turn to take a shower. The men would go last as we didn’t need as much time to get ready. My sister in law’s husband was outside on the back porch reading the paper and having some coffee. I started thinking this may be our last good chance.

I came out of my room and heard the bathroom door shut and the shower turn on. My sister in law kept the door cracked and I slipped my head and saw her wearing only a towel while she put on some makeup. I said, “wanna watch?” She looked at me and smiled and asked where her husband was. I told her he was comfortable on the back porch and we probably had a couple of minutes of privacy. We didn’t want to go into one of the rooms because we couldn’t see if someone was coming or not. Believe it or not we went out into the hallway, because it allowed us to secretly see her husband out the back window and listen to my wife in the shower at the same time. So there she was standing in front of me with wet hair and her body wrapped in a towel and I was in some gym shorts and a t-shirt. More comfortable this time, I lowered my shorts and boxers exposing my cock to her again. I could tell she was enjoying the show and she kept staring at my cock while occasionally looking out to make sure her husband hadn’t moved.

I asked her to show me her body and with no hesitation, she opened up her towel showing me her beautiful tits (about a C cup I guessed) and a nicely manicured bush. Her dark brown bush was so sexy, and I could believe she was showing it to me. It was so hot. I told her how much I loved seeing her pussy and tits and she closed up her towel and continued to watch. I asked her to let me see her ass and once again she turned her back to me and lifted up the towel exposing her sexy round ass with some adorable tan lines across her cheeks. I reached out and cupped one of her cheeks and she arched her back a bit and stuck her butt out a bit more for me. “Do you like?” she asked. I just confirmed to her how much I loved it. I kept stroking faster and scooted closer to her ass until the tip of my cock was actually touching her ass cheek. “Are you going to cum on my ass?” she whispered to me? We started whispering dirty things to each other. “Yes babe. I want to cum in your sexy ass”… “mmmm, I like that” she said. “You better hurry, we’re running out of time” she responded.

I wasn’t sure if was about to overstep my boundaries or not, but I decided to grab both of her ass cheeks and spread them apart. There we were standing in the hallway of this cabin, my wife in the shower, her husband on the back porch and her parents in their room getting cleaned up and my sister in law with her ass peeking out from under her towel, letting me spread her cheeks apart. I grabbed my hard cock and wedged the tip in between her cheeks and began stroking faster and faster. The tip of my cock was slightly pushing against her asshole as my hand stroked my shaft and would slap against her cheeks at the same time. I will never forget that image of me masturbating my cock while it was wedged in between her cheeks. “Cum for me baby” is all she said and a second later when I was about to cum, I pushed forward a little harder and guided the tip of my cock into her ass. She pushed back a little letting me know she wanted me in her. I began cumming and felt my cock pulsating and pumping cum in between her cheeks. When my orgasm subsided, I took a step back and saw my sister in law’s beautiful ass crack dripping with my cum. It began running down her leg and she cleaned some up with her towel and said I better go get cleaned up. And with that, she wrapped her self up and walked into her room and shut the door.

I returned to my room and a few minutes later the shower stopped. My wife came into the room and said “Your turn!”

We all got ready and had a great time the rest of the trip. Nobody ever suspected a thing. My wife’s sister and I had a few more fun encounters at later times, but I’ll save that for another story. We agreed never to have sex, but these secret masturbation games we played were so much fun. I’m so glad that email was sent to her.

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