light someone's fire vs melt someone's butter

light someone's fire

verb
  • To excite or arouse someone; to turn someone on. 

melt someone's butter

verb
  • To turn someone on; cause feelings of arousal. 

  • To appeal to someone's fancy. 

How often have the words light someone's fire and melt someone's butter occurred in a corpus of books? (source: Google Ngram Viewer )