punching bag vs scrapper

punching bag

noun
  • A person serving as an object of abuse. 

  • A tough bag, usually cylindrical, filled with air, sand, or other material, often suspended so that it swings freely, which is punched or kicked when practising sports such as boxing or martial arts. 

scrapper

noun
  • A person who fights doggedly, who exhibits indomitable will. 

  • A person who disposes of scraps. 

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