sugar baby vs sugar-plum

sugar baby

noun
  • A term of endearment; sweetheart. 

  • The younger recipient (usually female or a bottom) of interest from a sugar daddy or sugar mama, especially financial and romantic in an intergenerational relationship 

sugar-plum

noun
  • Term of endearment: sweetheart, darling. 

  • A round or oval sweet/piece of candy made of boiled sugar. 

How often have the words sugar baby and sugar-plum occurred in a corpus of books? (source: Google Ngram Viewer )