Nice one OP!
Honestly, with the way the cutscenes and animations are, I am not entirely sure I really want to see them. I don't want another Dragon Age Origins experience, or I'll need another brain bleach.
Of all the examples I've seen of sexy times in video games, I think I mostly prefer a sort of a prelude scene and then fade to black.
But I do think that in this game it really comes out of nowhere and is quite sudden, there's no real build-up towards it.
I don't think that there necessarily needs to be, sex can still be quite random.
Casual sex is fine, it's more about how it's everyone at the same time and how it's handled that feels weird.
I think this is more due to the fact that its an EA and the romance paths are not complete.