But that presumes that the girl changes her mind about the sex when she reaches his room, which seems strange.
In the example the girl usually don't just want sex but she wants sex while she's turned on and that brings her pleasure. Even in the case of asking directly for sex a girl would assume that the guy will engage in foreplay that puts her then in an emotional state where she will have pleasurable sex.
When a guy asks: "Do you want to come to my room for coffee" a girl might think "That's exciting and hopefully the night will end with great sex" but depending on how the interaction in the room goes it might or might not end up in sex.
I am assuming that the people involved have probably been out drinking and having fun and getting into an exciting emotional state beforehand.
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.
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