'Lucian Freud was thrilled when Leigh Bowery stripped naked': how a wild club kid became the great painter's muse / Lucian Freud's Ria leads Christie's Frieze week evening sale at PS11.8m / A $20 Million Lucian Freud Nude Makes Its Auction Debut / As Seen On 'Velvet Buzzsaw': Lucian Freud's Death-Defying Self-Portrait / What it's like modelling naked for Lucian Freud when he's your father / Lucian Freud, Francis Bacon and Frank Auerbach form part of Sotheby's summer exhibition