A friend of Shirou's who visits him every day to help him cook. Probably the closest person to Shirou over than his family or self-appointed "sister".
She seems shy and demure, but can be suprisingly willful when she puts her foot down and often goes out of her way to help Shirou, not only with cooking but even waking him up when he overlseeps in the shed after practicing his magic. She started helping Shirou after he burnt his right shoulder at his part time job and has stayed long after the burn healed.
She lives in an old mansion alongside her brother Shinji and her grandfather, a dark and foreboding place where the sound of chirping of various bugs can often be heard. Her relationship with Shinji seems quite bad at the moment, although she remains deferential to him.
A year younger than Shirou, she seems to have grown up slightly recently, and Shirou is taking more notice of her recently.
Overall, Sakura seems to be a normal, if quiet and delicate seeming girl with nothing to do with the world of the Mages.
However, just before the begining of the Grail War, she was seen by Archer and Rin talking to some mysterious forienger.
Sakura's brother and a braggart.
Despite officially being friends with Shirou, Shinji often insults and belittles him, with his comments on Shirou's burns leading to the latter leaving the club. Right now he just occasionally asks Shirou to do work he doesn't want to.
He often bullies those he percieves as weaker than him, like younger students and does not seem to get along well with his sister.
He's an annoying, slimy, egomanicial bully.
Despite all this, he's extremely popular with the girls at the Academy.