Katou Danzou is a fictional character from Fate/Grand Order, appearing as a Servant based on the legendary ninja and automaton associated with the Sarutobi clan. In the series, she is portrayed as a loyal, emotionless yet deeply caring ninja girl with mechanical traits, often serving as a protector and support figure. She acts with strict discipline and devotion to her master, while her hidden gentleness and desire to be useful give her a memorable, tragic charm within the Fate universe.