A painting of the teenage mistress Pablo Picasso picked up outside a Paris Metro station in 1927 has sold for $40 million at auction. La Lecture, which shows Marie-Therese Walter asleep in a chair, was sold to an anonymous buyer for double the expected price, the Telegraph reports. The painter charmed the 17-year-old Walter—28 years his junior—with the line: "I am Picasso. You and I are going to do great things together.'' The affair was long kept secret because Walter was underage, and because the painter was married.