concupiscence vs urge to merge

concupiscence

noun
  • An ardent desire, especially sexual desire; lust. 

  • the desire of a person's lower appetite, contrary to reason, which subjugates and inclines them to experience temptation and to give in to sin, due to the Fall and original sin. 

urge to merge

noun
  • A strong desire to form intense emotional connections, stereotypically associated with lesbians. 

How often have the words concupiscence and urge to merge occurred in a corpus of books? (source: Google Ngram Viewer )