tenderness vs urge to merge

tenderness

noun
  • a tendency to express warm, compassionate feelings 

  • pain or discomfort when an affected area is touched 

  • concern for the feelings or welfare of others 

urge to merge

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

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