As long as I want him I'm ok with this definetly
I have fucked my wife several times when she was asleep, and also my friend has fucked her too. Don't know if she was really asleep or played like it when he got into bed with us, but her pussy was hot and wet, so she must of liked him fucking her, then when he was done I would fuck her.
I don't invite anyone into my bed that I don't trust so hey you need a little, help yourself. I have woken up to hubby giving me oral, I look down, go for it baby. I think he is trying to wake me up in a sexy way. He always smiles, naughty boy! I also like to a good slow middle of the night session.
I might caress my wife to wake her for some sex, but just start humping away in her, no way. She's usually the one nudging me awake for sex anyhow.
I say if she has given you permission then do it! But as others have suggested i would at least wake her out of a deep sleep first. I speak from personal experience as i have had both positive and negative experiences with this. For example, my boyfriend had woken me up by kissing me and told me he was hard and wanted me i told him to go for it and went halfway back to sleep. Even when things started getting really hot i actually pretended to be more asleep than i really was because i liked him have total control and access to my bbody as i "slept". The experience was hot. Then there was another time where i was not woken up first and i awoke from a deep sleep to him on top of me pumping in and out. I was tottally turned off and told him to get off of me.
if i know the person/ have slept with them before its really hot.
Well, if she says she likes the thought and it is a fantasy of hers, i say go for it. If she wakes up and isn't as into it as she anticipated, then you stop. Being in a relationship is about exploring each others wants and fantasies whether they turn out well or not. My boyfriend told me it was one of his fantasies to wake up to me on top of him putting his cock in me. So, I did it. He loved it.