In Your Sleep

Amongst other things folks snore, walk, eat and possibly have sex in their sleep (sexomnia):

More than 92% said they had experienced multiple episodes of sexomnia, and a variety of sexual behaviors were reported, including 105 respondents—24 women and 81 men—who said they had had sexual intercourse while sleeping.

These are results from an anonymous internet survey so they may not be worth any more than spam.

I think these folks are just reporting fantasies, conflating sleep with the results of drinking and/or drug use, or remembering their wet dreams.