crap one's pants vs piss

crap one's pants

verb
  • To defecate into one's pants or other clothing. 

  • To be extremely frightened. 

piss

verb
  • To urinate. 

  • To rain heavily. 

  • To discharge as or with the urine. 

  • To achieve easily. 

intj
  • Expresses anger, disappointment or dissatisfaction. 

noun
  • The act of urinating. 

  • Urine. 

  • An intensifier. 

  • Alcoholic beverage, especially of inferior quality. 

How often have the words crap one's pants and piss occurred in a corpus of books? (source: Google Ngram Viewer )