drop off vs seek one's virtuous couch

drop off

verb
  • To fall asleep. 

  • To fall. 

  • To deliver; to deposit or leave; to allow passengers to alight. 

  • To lessen or reduce. 

seek one's virtuous couch

verb
  • To go to bed: to lie down to sleep. 

How often have the words drop off and seek one's virtuous couch occurred in a corpus of books? (source: Google Ngram Viewer )