love up vs lovebird

love up

verb
  • To demonstrate affection (on somebody). 

  • To demonstrate affection for; treat in a loving way. 

  • To make love to. 

  • To accept; to love wholeheartedly. 

lovebird

verb
  • To express romantic affection openly. 

noun
  • Any small parrot from one of the nine species within the genus Agapornis. Sometimes they are kept as cage birds and are noted for their affection towards each other. 

  • One of the members of an openly affectionate couple. 

How often have the words love up and lovebird occurred in a corpus of books? (source: Google Ngram Viewer )