The young lady of a famous magician family, she is calm and willful at the same time, probably because she is the incarnation of the hero Sima Yi. If you think about doing anything to her without her consent, be careful, you might get attacked by her followers.
If you know the King of Camelot, she is another side of her. The King of Storm, she will rip through anything with her dark storms with brutality. But if you make her like you, that brutality may turn into something worthwhile.
When you are chosen to become a Master to join the Holy Grail War, the first thing you need is your Servant. They will act as your sword and shield, helping you overcome any obstacles and lead you to become the winner of the Holy Grail War.