get together vs pair off

get together

verb
  • To start dating; to start being a couple. 

  • to agree 

  • to accumulate, to gather 

  • to meet, to gather together, to congregate 

  • Used other than figuratively or idiomatically: see get, together. 

pair off

verb
  • To join two people into a relationship. 

  • To separate into groups of two. 

How often have the words get together and pair off occurred in a corpus of books? (source: Google Ngram Viewer )