butt-fucking vs horse piss

butt-fucking

noun

  • anal sex 

adj

  • Engaging in anal sex 

horse piss

noun

  • Urine from a horse. 

  • Lies, untruths. 

  • An alcoholic beverage 

  • beer 

  • Used other than figuratively or idiomatically: see horse, piss. 

  • Nonsense, gibberish. 

  • An unpalatable alcoholic beverage 

How often have the words butt-fucking and horse piss occurred in a corpus of books? (source: Google Ngram Viewer )