日久生情 [－－－－]

Jyutping jat6 gau2 sang1 cing4
Pinyin rì jiǔ shēng qíng

Definitions (CC-CEDICT)
  1. familiarity breeds fondness (idiom)
Definitions (粵典–words.hk)
  1. x
Definitions (Wiktionary)
  1. phrase, idiomatic
    familiarity breeds fondness; love develops with time
  2. phrase, idiomatic, slang, vulgar
    to develop fondness after sleeping with each other for a while