A female nude painted by Francis Bacon in 1963 will lead Christie’s London auction of post-war and contemporary art on Feb. 14, where it is expected to fetch around $28 million. “Portrait of Henrietta Moraes” depicts Bacon’s friend and former lover of Lucian Freud in a large, vibrant work which Francis Outred, head of post-war and contemporary art in Europe, called “one of the most seductive and sexually charged paintings I have ever encountered by Bacon.” Bacon’s depictions of “bon vivant” and London socialite Moraes were his first to seriously consider the female form, although he is most often associated with the male nude. Art critic David Sylvester once said: “Bacon’s lack of personal erotic interest in naked females did nothing to prevent these paintings from being as passionate as those of the male bodies that obsessed him.” The artist never painted his subjects from life, and so asked photographer John Deakin to take a series of pictures from which he could work. 1963 is considered an important year for Bacon, whose works have become coveted by some of the world’s wealthiest collectors willing to part with fortunes to own them.