henchman vs lap dog

henchman

noun
  • A person who supports a political figure chiefly out of selfish interests. 

  • A loyal and trusted follower or subordinate. 

  • An assistant member of a criminal gang. 

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. 

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