Yes I agree Luncheon on the Grass or The Bar at Folies Bergeres:
He was famous and greatly respected by the impressionists Monet, Renoir, Degas, et al.. He was in terrible pain from syphilis/rheumatism later in life.
Manet became the friend and colleague of Berthe Morisot in 1868. She is credited with convincing Manet to attempt plein air painting, which she had been practicing since she was introduced to it by another friend of hers, Camille Corot. They had a reciprocating relationship and Manet incorporated some of her techniques into his paintings. In 1874, she became his sister-in-law when she married his brother, Eugene.