After you have seen more of Lena Dunham’s body than that of any other serious actress, there’s always the question of how you will greet her in the flesh, clothed and social, as at the spectacular HBO party thrown for the dynamic Girls quartet at Cipriani 42nd Street this week. Guests had just come from Alice Tully Hall, from a preview of an opening double episode, and a second, the first featuring Dunham’s Hannah sunbathing her most private part in Montauk. That moment gave pause to a more demure Maggie Gyllenhaal who revealed that she shows skin in her new series, “The Deuce,” in which she plays a prostitute. “I come from an older generation of women,” said Gyllenhaal with regard to Dunham’s unashamed nakedness and frank display of sexuality. No matter, everyone applauds Dunham’s brilliance as a writer and actress: her brave approach to normalizing the female image in every perfect imperfection is simply groundbreaking.