That is the sound of real fun. GREAT (even when she watched TV during that 1:44 min).
This makes us more horny than any other fucking showing no reaction in the faces.
The dick is almost certainly in her ass, and the "I don't like being fucked in the ass" face is a universal truth. Pleasure is not easily mistaken. Either she hates it or she's a really good actress and is "supposed" to hate it.