Green’s Dictionary of Slang

1. (US Und.) a venereally diseased penis; a severe case of gonorrhoea.

1950

Goldin et al. DAUL 130/2: Lulu. The male organ freshly infected with gonorrhea; a bad case of gonorrhea.

2. the female genital area.

2002

Marian Keyes in Penguin UK 🌐 Apart from the hair on your head, strive at all time to be entirely hair-free. If you really must you can have a little ‘landing strip’ on your lulu, but other than that, everything must go!