penchant vs soft spot

penchant

noun
  • Taste, liking, or inclination (for). 

  • A card game resembling bezique. 

  • In the game of penchant, any queen and jack of different suits held at the same time. 

soft spot

noun
  • A sentimental fondness or affection. 

  • A point of vulnerability in a defence. 

  • A fontanelle. 

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