I apparently have sexsomnia (it's a kind of sleepwalking, which I also, but with sex). Happened with my ex-wife (twice I think) and she was pissed off because I raped her while she sleeps. The worse is that I didn't even remember, it's like being half-aware of what was happening.
As I said, ex-wife. My current GF finds it pretty hot. I already did some sexsomnia with her and some actual sex while she is sleeping (or at least in the beginning). Those are 100% the best sexual activities we have. I love to wake her up mid sex.
Pic is related.