lap dog vs ratfink

lap dog

noun
  • A person who behaves in a servile manner, such as a sycophantic employee or a fawning lover. 

  • A small toy dog, kept as household pet, whose light weight and companionable temperament make it both suited and disposed to spend time resting in the comfort of its master's lap; a dog bred to behave in this manner. 

ratfink

noun
  • A dislikable or contemptible person. 

  • An informer or spy; a traitor. 

verb
  • To inform on; to betray. 

How often have the words lap dog and ratfink occurred in a corpus of books? (source: Google Ngram Viewer )