Have you ever had two sexual partners in the same night who didn't know about each other?

Never had two women in one night but I did get cross dressed and sucked four cocks in one night.  I put an ad on Craig’s list and made it very clear I was being slutty and looking to suck multiple cocks so they all knew.  

I had three in one night. I wasn't expecting the other two to be around.

As a former Exotic Dancer and straight Male Ballet Dancer I not only slept with two different women on the same night but oftentimes, with two at the same time.  In my privatized former world, this was actually not such a big deal as with Dancers, sex is an 'entitled' cathartic release from what we did.  Nonetheless, as a male dancer I certainly didn't go about the studio thumping my chest about it as this is beyond rude and disrespectful.      

Yes, I've done this many times.

No, no, no 😱

Yes, but second or third playmate almost always knows.

Oh yes several times I had sex with two to three women in a day that none knew about the other.

Yes, once. My wife and I had an open marriage and she actually talked our neighbor into going on a date with me. We went on the date and ended up at a local motel. When I got home my wife was interested in the details and we ended up having sex. She went down on me before I could shower. This isn't really what the question was regarding not knowing...sorry.

I've done it on many occasions

Yes, a few times.

Short answer: No.

Closest I've come to that is almost having sex with two women within a 24 hour period, on consecutive nights. I did have sex with the first woman, but I wasn't able to close the deal with the second. She and I had known each other a long time and really liked each other, this particular night featuring a very long makeout session and some clothing removal before fizzling out.

But this outcome was probably for the best: she shared at one point being grossed out by the idea of oral sex (giving and receiving). I just can’t even imagine that perspective, so it might have ended up a deal killer for me anyway, at least for any kind of ongoing sexual relationship.

I was fortunate to have scored a hat trick twice in my life. Both stretched from afternoon until late that night, at three different locations. Still jackoff thinking back to those days.

Yes. As my wife had her girlfriend, I was given freedom to play. She didn't know who I was with, but she knew I had a woman. One afternoon my wife went to her girlfriends for the evening for dinner and a grind. I called my lady friend, and she said I should come over awhile. I made the call, then the house call, and I was home all while my wife was out. I had showered and when she came home, she was horny, and we had sex without her suspecting anything.

I hooked up with a guy at a party then after the party hooked up with my friend's brother and his roommate, with the other guy's cum still inside me.

Yes. Shamefully, I even once slept with a friend's husband, then both of their sons (they were over 18) all within maybe a 3-hour time span without showering in between and neither of them realized that I was just with someone before them or if they did, they didn't say anything. Some things you're better off left not knowing, but at least everyone was happy and got what they wanted.

Lots of times, often I would have sex with men, then go home and have sex with my wife. Sounds fucked up, but she was a horrible wife who did everything she could to break me. I finally got up the courage to leave her.