I remember reading the novel and the time they switched roles was so awkard. "You are gonna fuck me baby" (nothing wrong with seke couples).... It was not such a bad novel, but towards the end it turned kind of crappy, but I still liked it.
i didn't find it awkward. in his last relationship it was more like he was never allowed to and now he is given permission to experiment basically. it made since and allowed progression in the relationship. but that's just me.
Maybe he impotent thats why he fucks with toys