侍妾始终不如正妃
[shì qiè shĭ zhōng bù rú zhèng fēi]
'侍妾始终不如正妃' refers historically to a concubine never being equal to the principal wife ('the official consort'), alluding to the historical context where hierarchical positions exist, especially within ancient marital relationships, indicating inferiority or regret related to status.