Fate/stay night (2006)

S1E2 Fateful Night

Rin is struggling with her current servant and feels frustrated by her inability to summon a stronger one. Meanwhile, at school, Ayako has enlisted Shirou to watch over Sakura’s brother, Shinji Matou, who has been causing trouble in the archery club. Ultimately, Shinji manipulates Shirou's kindness, forcing him to manage the dojo for the club. While Shirou is busy cleaning, he hears a commotion outside and goes to investigate, only to stumble upon a fierce battle between two servants.