The Heir

Li Jinshui, head of the Li family's eighth branch, is Li Zhen's grandfather and a master ink craftsman who trains her for three years in the family's secret techniques. Though gruff and demanding, his guidance shapes her into a worthy successor, and he performs an ancestral ritual when she produces supreme-grade lampblack. Their bond deepens throughout the series as they work together to restore the family's honor.

After his family's downfall, Luo Wenqian is protected under the false identity Qi Jiu, and over years of shared hardship he and Wang Cuiqiao develop a deep sworn-sibling bond. She helps run the Yihousheng pawnshop that fronts his covert re-entry into the ink trade and repeatedly warns him against reckless moves that could expose or endanger him.

Wang Rujun, matriarch of the seventh branch and de facto head of the Li clan, takes a special interest in Li Zhen from childhood, calling her the clan's treasure. Despite the family's harsh treatment of the exiled eighth branch, Wang Rujun repeatedly extends protection and opportunity to Li Zhen, and the two share a warm, mentoring rapport as Li Zhen rises in the ink trade.

Du Qiu'e appears to be Li Zhen's mother, a steady presence who urges her children to move past the family that abandoned them and rebuild their lives after the eighth branch's expulsion. Reviewers note the mother-daughter bond as a quiet, supportive thread running through Li Zhen's rise.

Li Jingdong was crippled in the fire that destroyed the tribute ink, a disaster caused by the negligence of Li Zhen's father, and he initially directs his grief and rage at Li Zhen's branch of the family. He is one of the harshest voices demanding the eighth branch's expulsion and humiliation. Over time his hostility softens as he witnesses Li Zhen's talent and resolve, and their relationship gradually heals.

Tian Jiangyue, widow of Li Jingqi who died in the tribute-ink disaster, blames Li Zhen's father for her husband's death and becomes one of the eighth branch's most vindictive tormentors. She strikes Li Zhen's elderly grandfather, seizes family dowry items, and repeatedly tries to bar the family from clan support. Her antagonism toward Li Zhen persists as a recurring source of household conflict.

Tian Ronghua, Tian Benchang's sister, befriends Li Zhen as a child and pools her own savings to help the struggling eighth branch. Their friendship remains a genuine, uncomplicated source of warmth for Li Zhen amid the family scheming surrounding her, standing in contrast to the hostility from other Tian relatives.

Li Zhengliang is Li Zhen's brother, sharing in the eighth branch's fall from grace and years of hardship after their expulsion from the clan. He supports her decision to return to the main workshop and rebuild the family's ink business, standing as one of her steadiest allies within the immediate family.

Luo Hanzhang, patriarch of the rival Luo family and creator of the famed Ziji Dragon Light Ink, is Luo Wenqian's father. He is initially strict and image-conscious, furious when he learns his son has been mingling with the rival Li family as a child. Their relationship carries the weight of the Luo family's later ruin and Wenqian's covert struggle to restore its fortunes.

Li Jinshui and Wang Rujun are senior figures of the Li clan who share mutual respect built over decades. When the eighth branch loses its tribute-ink status and is expelled, Jinshui entrusts the family's workshops to her, though he refuses her urging to preserve his secret recipes, choosing instead to let them die with him.

Li Jinhe manages the main Li workshop's affairs and acts as a clan intermediary, delivering gifts and stern warnings to the eighth branch on the family's behalf. His dealings with Li Zhen are formal and cautious, reflecting the clan's conditional, transactional relationship with her branch even as tensions ease.

Tian Benchang and Tian Ronghua are siblings within the Tian family, shown as children pooling their savings together to help the struggling Li family. Both later become entangled in their father's schemes against Li Zhen, though Ronghua's warmth toward Li Zhen contrasts with the pressure placed on Benchang to betray her.

Li Jinshui, head of the eighth branch, and Li Jingdong, of the sixth branch, are members of the wider Li ink clan whose relationship grows strained after the tribute-ink disaster. Jingdong's grief and blame toward Jinshui's branch color their interactions, though both remain bound by clan loyalty and the shared legacy of Li Ink.

Zhao Jin appears in the main cast of The Heir but available sources do not clearly describe this character's specific relationship to Li Zhen or their role in the story.

Xiao Man is listed among the main cast of The Heir but available sources do not clearly describe this character's specific relationship to Li Zhen or their role in the story.

Yan Xianglan is listed among the supporting cast of The Heir but available sources do not clearly describe this character's specific relationship to Li Zhen or their role in the story.