fall asleep vs seek one's virtuous couch

fall asleep

verb
  • To pass from a state of wakefulness into sleep. 

  • To be affected by paresthesia; to go numb. 

  • To die (often seen on gravestones). 

seek one's virtuous couch

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

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