Azrael vs Grim Reaper

Azrael

name
  • The angel of death in Catholic and Orthodox Christianity, and in Islam. 

Grim Reaper

name
  • A personification of Death as an old man, or a skeleton, carrying a scythe, taking souls to the afterlife. 

How often have the words Azrael and Grim Reaper occurred in a corpus of books? (source: Google Ngram Viewer )