Vampire Knight Episode 7

During his target practice, Zero reveals that he can sense Yuki's feelings for Kaname through her blood. In a flashback, Yuki recalls when Kaien adopted her and that she was initially fearful of Kaname before becoming close to him. When Kaien brought Zero into the household, he explained to Yuki that his entire family had been killed by a vampire. Shortly afterwards, Kaien established the Cross Academy with the Day Class and Night Class, which infuriated Zero. After class one day, Yuki attempted to visit Kaname, and saw him drinking the blood of Ruka Souen. Afraid, Yuki ran away. In the present, Zero finds Yuki asleep and is tempted to drink her blood when Kaname appears. He explains to Zero that the only reason he has not killed him is to keep him alive for Yuki's sake.