second string vs unfun

second string

adj
  • Not as good; of a lower quality or condition. 

noun
  • A unit of players which is considered to have a secondary level of talent and which usually plays after the first string. 

unfun

adj
  • Not fun. 

noun
  • Lack or absence of fun; funlessness. 

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