过期爱人我忘不掉
[guò qī ài rén wŏ wàng bù diào]
Translating to 'Expired love that I cannot forget'. This portrays a bittersweet sentiment towards a former relationship or love interest that persists despite its conclusion, revealing lingering emotions such as regret, longing, and unresolved feelings toward an ex-lover who continues to impact the holder of this nickname.