Fujimaru Ritsuka (Female) is the female protagonist and Master of Chaldea in the Fate/Grand Order series. She wears the Polar Chaldea Uniform, a specialized jacket used for purification and recovery during intense battles, such as in Lostbelt scenarios. As the last Master of Chaldea Security Organization, she rayshifts to resolve humanity's incineration crisis, summoning and commanding Servants to restore Proper Human History. Known for her strong bonds with Servants, quick thinking, and unyielding spirit, she navigates complex threats like Lostbelts and singularities, often showing compassion even to adversaries. In events like the British Lostbelt, she interacts closely with figures like Oberon and Morgan, demonstrating her adaptability and leadership.