Angel tends a Japanese Peace Lily throughout the film and even buys one for Constable Butterman. The idea of a highly-trained killing machine tending a plant to give himself some sort of fulfilment is taken for Leon, where Leon obsessively nurtures a houseplant. Of course, Mathilda replaces the plant as Leons best friend, much as Danny replaces the Japanese Peace Lilly as Nicks closest pal. It could only be more complete a reference if Leon bought one for Mathilda, or destroyed his own on the head of a very large man. The Leon reference is a reference to Jean Pierre Melvilles 1967 film Le Samourai, where the title character owns only a bare apartment and a canary. Its one of Wrights favourite films.