Hiding in plain sight in Asakusa, Tamayo is a centuries-old demon who defies her very nature by working as a gentle, reclusive physician. Her elegant kimono and quiet demeanor conceal a brilliant mind devoted to medical research, surviving only on blood willingly given by donors rather than taking lives. Though she carries the deep sorrow of a tragic past, her true purpose is to find a cure for demonhood and aid those who wish to see Muzan Kibutsuji fall.