erogenous zone vs pee-pee

erogenous zone

noun
  • A part of the human body that is particularly responsive to sexual stimulation. 

pee-pee

noun
  • The penis or vulva; genitalia. 

  • Urine. 

verb
  • To urinate. 

How often have the words erogenous zone and pee-pee occurred in a corpus of books? (source: Google Ngram Viewer )