Sex with some stranger or new partner has its positives. It adds to the experience, even the thought of such a forbidden for many is arousing, counting on the stamina and imagination of the partner. Sex in the bar is somewhat relaxing and not as luscious as on the bed. This couple's anal sex and caresses deserve praise and encouragement.
The girl blew the guy off because he can't kiss or fuck. He's still a virgin. So the mother is right - the daughter should help her foster brother become a man. And mama wouldn't wish no harm on him. Lucky the kid's got such advanced parents.