spooky vs unfrightening

spooky

adj
  • Eerie, or suggestive of ghosts or the supernatural. 

  • Spooked; afraid; frightened. 

  • Unpredictably excitable; skittish (used especially of horses). 

unfrightening

adj
  • Not frightening. 

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