What is a short summary for the story, Nunc Dimitis?

Lionel Lampson is a British aristocrat who fancies himself a true citizen of the world, a sophisticate and art collector, a ladies' man and a dashing fellow. He becomes silently enraged when one of his social acquaintances, Gladys Ponsonby, tells him that the woman he's been dating, Janet de Peagia, thinks him a crashing bore. Cunningly, Lionel arranges with a popular artist to paint Janet in his usual manner: first a nude, then a fully-clothed figure. Lionel then washes off the top layers of paint with a solvent to reveal a nude Janet. He invites his friends to a special dinner party, where he suddenly and shockingly reveals the nude portrait. By this time, he's already fled for a "vacation." Upon his return to London, Lionel learns his friends are not amused; they think him a creep. He feels even worse when he gets a forgiving note from Janet.