It’s very sad to see how many people climb on their high horse and believe there is a sexualization of a minor .Natalie’s character is a young girl with a bad childhood , bad parents and a big trauma who desperately cling on Léon because he saved her life and cares for her . Something she never had in her life before . She tries so hard to grow up quickly ( hence the smoking and swearing ) and he is childish ( represented by drinking milk ) . Yes , there is sexual tensions a time but it never crosses the line and without it would make the movie very different . For me it’s a masterpiece.