flip side vs other side

flip side

noun
  • The converse; opposite, usually negative, inherent aspects or consequences of something. 

  • The reverse, in contrast to the obverse. 

other side

noun
  • Used other than figuratively or idiomatically: see other, side. 

  • The afterlife, as a supernatural realm inhabited by spirits of deceased people. 

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