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3.
Sleep sex, or sexsomnia, is having sex while you're asleep. It is related to sleepwalking or sleep eating. The person who does it has no recollection of it in the morning, though they may have a feeling of sexual satisfaction.

Little is known about it, as there needs to be more research on it, but it seems to occur most often in people who have suppressed their need to have sex during the day, or who have an unfulfilled love for someone.

Because of the proximity of other sleeping family members, father-daughter or brother-sister coupling may result. It is dangerous to wake a sleepwalker, so the best method of handling the situation is usually to simply wait until it is over.
My brother walks in his sleep, and lately he has been getting into my bed. I'm wondering if he's going to start having sleep sex one of these nights.

I woke up in the morning feeling wet between my thighs, and a large wet patch on the bed. I'm wondering if I indulged in sleep sex during the night.

In the morning I woke up in my father's bed, feeling as though I had just had sleep sex. My father had my lipstick smeared on his lips and cheek, but he does not have any memory of it.
by Group of Friends May 19, 2011
 
1.
the act of sleeping naked next to your best friend and he/she is also naked and you wake up in the morning and find her or him on top of u with the penis inserted into the pussy.
i woke up with my best friends dick in me and we dont know how it got there damn that sleep sex
by jpotts93 August 06, 2009
 
2.
A phenomenon where someone subconsciously displays sexual activity with another human, a pillow, the bed or anything around that is available.
Jimmy: shucks i got dumped again
Nami: aw u must've sleepsexed her again
by lucidwolfe June 04, 2010