"I'll put you all out of work someday! Yes I will!"— Zhong Yi Rou(src)
Zhong Yi Rou was a sickly gemcutter, known to frequent Xiansai at at least one point in her life. Responsible for creating the Gem of Efficacious Toxin and Iceblink, she created these gems in order to replace their predecessors (poisons and a certain splint mail, respectively), but with modifications to improve the quality of the final product. She was also known to broadcast her intentions of creating these replacements, including antagonizing the poison makers whose work she intended to replace with the Gem of Efficacious Toxin.