Song Chengmei

Sòng Chéngměi (宋成美) was born as the bastard son of Chang Cian and a servant of the Yueyang Chang sect who was killed after giving birth to him. He was then made a servant of the sect and abused heavily, until he met Song Lan by coincidence and was taken in as his little brother. He was later on given the title The Onyx and eventually joined Wei Wuxian's Imperial Harem.