demonly vs diabolical

demonly

adj

  • Of, relating to, or like a demon; demonic. 

adv

  • In a manner befitting or like a demon. 

diabolical

adj

  • Of or concerning the devil; satanic. 

  • Extremely wicked or cruel. 

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