[1][3] Following a number of jobs working as a teacher and a copywriter, she started her career as a writer after the Second World War by entering the weekly competitions run by the New Statesman.

Naomi herself was particularly fond of the 1993 publication The Mardi Gras Cat, in which she presented a carefully selected gallery of feline personalities, each immortalized in poetry.

Lewis taught poetry appreciation and creative writing at London's City Literary Institute for many years, and due to popular demand went on doing so well past the official age of retirement.

She complained in a letter to the Evening Standard, "What moral right have humans to lay on sensitive creatures the sufferings of their own vanity, greed and cowardice, and a host of various sins?"

Due to her habit of rescuing stray cats and injured pigeons around her home her Bloomsbury neighborhood, she was featured on the BBC program London Identities and made the subject of a national newspaper article.