pocket pool vs self-pleasure

pocket pool

noun

  • The act of manipulating one's genitalia through a trouser pocket; masturbation. 

  • A variation of the game of pool. 

self-pleasure

noun

  • masturbation 

verb

  • To pleasure oneself; masturbate. 

How often have the words pocket pool and self-pleasure occurred in a corpus of books? (source: Google Ngram Viewer )