皇后不死你永远是个妃
[huáng hòu bù sĭ nĭ yŏng yuăn shì gè fēi]
Literally translating to 'as long as the queen lives, you will always be just concubine.' From ancient times, where the emperor was only able to officially have one empress even though many wives and consorts exist, reflecting the longing and bitterness that someone has when feeling unattainable in rank, status, or affection from another, usually higher ranking or more desired, person.