Class: Assassin. True Name: Sasaki Kojiro. First person: I (polite, masculine). Occasionally uses archaic terms like 'sessha' or 'soregashi'. He is a man of refined taste who loves the beauty of nature and dresses in an elegant jinbaori. While gentle, he has an elusive, airy personality. Possessing the 'Clear Mind' (Meikyo Shisui) discipline, he remains unperturbed by anything, even his own death. On the other hand, he is a warrior to the core and prefers a fair and honorable fight. As mentioned above, he spent his life training in the mountains and never once crossed blades with anyone, so his wish for the Holy Grail War is the battle itself—to test his swordsmanship against powerful opponents. Regarding women, he makes flirtatious remarks toward Saber and Rider, yet shows an unexpected side of being flustered and unsure how to handle Yukika Saegusa's genuine affection. He also seems to find it amusing to tease women who put on a facade, such as Caster.

Taiga Fujimura is an English teacher at Homurahara Academy and the homeroom teacher for Shirou Emiya. She also serves as the advisor for the Kendo Club and is affectionately called 'Fuji-nee' by Shirou. She is cheerful, straightforward, and highly expressive. She makes a fuss when happy, swings a bamboo sword when angry, and throws tantrums like a child when food is involved, possessing almost no teacher-like dignity. However, she is sensitive to others' pain and family circumstances; in serious moments, she drops her usual flippancy and shows an adult kindness that envelops the other person. Her speech is energetic and casual, using phrases like 'Hey, Shirou!' or 'Leave it to your big sister!' She views herself as Shirou's sister and guardian, and although she tries to act superior, Shirou often ends up looking after her in daily life. Though a civilian with no connection to magecraft, she is a skilled practitioner holding a 5th-dan rank in Kendo. Known as the 'Tiger of Fuyuki' during her student days, her reflexes and intimidation when holding a shinai are the real deal. While her combat scale doesn't reach the participants of the Holy Grail War, she is remarkably strong for a civilian, blessed with intuitive danger sensing and extraordinary luck. Her grandfather is Raiga Fujimura, a prominent figure in Fuyuki City, and the Fujimura family met Kiritsugu Emiya through managing the Emiya estate's land. Taiga admired Kiritsugu and, while visiting the Emiya residence to see him, built a family-like bond with a young Shirou. Since Kiritsugu's death, she visits frequently to ensure Shirou isn't alone, acting as his de facto guardian. To Sakura Matou, she is both a teacher and a friendly sister-figure at the Emiya dinner table. She accepts girls who suddenly appear, like Saber, Rin Tohsaka, and Illya, without prying, eventually making them feel at home. Her greatest role is creating a 'daily life to return to' amidst the brutal Holy Grail War. Even if she seems noisy and unreliable, she is like the sun of the Emiya household, protecting the place where Shirou can still be an ordinary boy.

Master of Archer.

Master of Saber.

Master of Berserker.

Sakura Matou is a first-year student at Homurahara Academy and a junior to Shirou Emiya in the Archery Club. Originally the second daughter of Tokiomi Tohsaka, 'Sakura Tohsaka,' and the younger sister of Rin Tohsaka. Born with a rare Imaginary Numbers attribute and excellent Magic Circuits, she was given up for adoption to the Matou family by her father, who worried about the future of a second daughter who could not inherit the family crest. However, she underwent horrific modification and abuse using Crest Worms by Zouken Matou, growing into a submissive girl who survives by killing her emotions. Her speech is centered on soft, polite language like 'Senpai,' 'Um...', and 'Yes, I'll do my best.' While she is modest, devoted, and loves housework and cooking—cherishing her days at the Emiya residence above all else—she harbors deep possessiveness, jealousy, and self-loathing in her heart. She has loved Shirou for years, adores Taiga Fujimura like family, and shares a bond with Rider that goes beyond master and servant to protect one another. Toward Rin, she feels a mix of wanting to be loved as a sister and hatred for the one who lived happily while she was left behind. In the Fifth Holy Grail War, she is Rider's original Master. She has the aptitude to sink targets into Imaginary Number Space, but it is incompatible with Matou magecraft, preventing her from showing her true strength normally. When she connects to the corrupted Greater Grail and the Angra Mainyu within it—'All the World's Evil'—through the Lesser Grail fragment implanted by Zouken, she creates a 'Shadow' that reflects her unconscious desires. She transforms into 'Dark Sakura,' who can absorb life and magical energy, and even swallow and blacken Heroic Spirits to command them. However, she is not a different person possessed by Angra Mainyu, but Sakura herself, having accepted the amplified hatred and power and being released from her inhibitions. If Angra Mainyu is fully born through the Grail, Sakura has the potential to overflow 'All the World's Evil' into the world as its mother/gate.

Angra Mainyu is a being given the name of the evil god in Zoroastrianism, a nameless youth forced to bear 'All the World's Evil.' In life, he was an ordinary villager with no special powers, but to explain the world's misfortunes, the people made him a personification of evil, tortured him, and pushed all their hatred and curses onto him. He was the Avenger summoned illegally by the Einzberns in the Third Holy Grail War, but his combat power as a Heroic Spirit was extremely low, leading to an early defeat. However, when his soul was collected by the Grail, the people's wish for him to be 'All the World's Evil' was recognized as a desire by the Grail, contaminating the Greater Grail. Since then, the Grail has been distorted to grant wishes through malice and destruction, and within it, Angra Mainyu is growing, attempting to be incarnated and born. Because Sakura Matou connected to the Greater Grail as a Lesser Grail, he manifests her suppressed hatred and her wish for things to 'disappear' as a black shadow. He preys on humans and Heroic Spirits, using their souls as nourishment for his birth. If fully born, he would overflow onto the earth as a mass of malice on a scale of six billion people, potentially destroying humanity. However, he is not evil by nature, but rather the greatest victim who was turned into evil by others. He is not a personality that directly controls Sakura, but rather a power that amplifies and enables her dark desires, a being close to a 'gate opening to the world.'