BOB vs downstairs

BOB

noun
  • Vibrator (device designed to stimulate a woman's genitals). 

adj
  • Back-of-the-book; denoting those stamps in a catalogue that are not used for the payment of regular postage fees, and are displayed separately in the catalogue after that listing; the division between these two groups varies with the publisher. 

downstairs

noun
  • The genitalia. 

  • The lower floor of a house, at ground level; especially the servants’ quarters. 

adj
  • Located on a lower floor. 

adv
  • Down the stairs. 

  • In or to hell. 

  • Regarding the genitalia. 

How often have the words BOB and downstairs occurred in a corpus of books? (source: Google Ngram Viewer )