Li Kei, also known as Rikei in the original Japanese, is a minor supporting character in the manga and anime series D.Gray-man. He is a member of the Science Division at the Asian Branch of the Black Order. In terms of background, Li Kei is a researcher who works alongside other scientists such as Lou Fa and Shifu, contributing to the Order’s efforts to understand and develop Innocence, the divine substance used by exorcists.

His personality is not extensively explored in the series, but he is portrayed as a diligent and competent member of the research team, focused on his duties. His primary motivation is to support the Black Order’s mission from a scientific standpoint, aiding in the fight against the Millennium Earl and the Akuma.

Li Kei’s role in the story is limited to that of a background scientist; he appears in scenes set within the Asian Branch, providing technical assistance or guidance to the exorcists. He does not take part in combat or possess any special abilities beyond his scientific expertise. His key relationships are with his fellow researchers, particularly Lou Fa and Shifu, with whom he collaborates closely. He has no notable character development over the course of the series, remaining a static figure within the Black Order’s support structure.