Matou Sakura

One of the main heroines of Fate/stay night.
With her long, lustrous hair, soothing smile, and (secretly) dynamite body, by all rights she should be the star heroine. Too bad she's an unfortunate girl who just sort of fades into the scenery.
The heroine who symbolizes a peaceful daily life… or so it would seem at first. Perhaps due to some mistake, she actually suffers the most out of anyone in every route.
Of course, that's only natural, seeing as how her initial concept was an “Asagami Fujino type.” She never had a chance at avoiding bloodshed.
As Shirou's junior by one year, the path to their first meeting was relatively convoluted.
Four years ago, sometime around April, Sakura saw Shirou persistently attempting the high jump.
Then, later that same year they actually met for the first time when Shirou came over to the Matou residence. From that point on she worked hard to greet Shirou every time he came over, until finally a year and a half ago she started going over to the Emiya residence herself to help him out.
Afterward, she gradually grew accustomed to the Emiya residence, and due to Fuji-nee's influence became a more cheerful, energetic Matou Sakura.
She has a quiet personality, and all things considered is exceptionally patient and persevering.
Basically, she is a worrisome girl that never resents others (not even Shinji or Zouken), and always blames herself for everything.
The solitary exception to this rule is Rin, because the two of them are so similar. I guess she's only capable of being honest with herself, or someone almost exactly like herself, yeah.
As everybody knows, she seems passive, but when she does do something she devotes herself to it completely. She's the girl in the story most suited to using seduction to get what she wants.
Though she's always exuding an obvious aura of “senpai-adoration,” it's hard to say if the all-important object of her affection, Shirou, has actually noticed or not.
A devilish woman with a strong maternal instinct, she'll pamper a man to the bitter end and ruin him with her charms. But, just like Hariti…
The most popular among the staff, maybe. “A heroine at the end of her rope,” “A somehow distorted heroine,” “A heroine that loves her big brother” …and so on. She can count on the fanatic vote, right?

Fate/side material: Fate Encyclopedia